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Cu-catalyzed, Mn-mediated propargylation and allenylation of aldehydes with propargyl bromides

Cu-catalyzed, Mn-mediated propargylation and allenylation of aldehydes with propargyl bromides Introduction attracting a great deal of attentions [14–23]. Numerous Propargyl and allenyl groups are not only valuable build- methods have been established by using propargyl hal- ing blocks for further manipulations and organic trans- ides and metals to produce the nucleophilic character of formations in organic synthesis [1–7], but also sever as the propargyl metal species [24–26]. When the nucleo- active structural moieties in plentiful functional mol- philic receptor is an aldehyde, the homopropargyl alcohol ecules which are important in bioactive molecules, phar- can be obtained by the nucleophilic addition of propar- maceuticals agents and natural products [8–13]. Thus, gyl metal species and aldehyde [27, 28]. Variety of metals, this interesting and promising synthetic method has been including In [29–31], Sb [32], Pb [33], Ti [34], Cr [35], Ga [36], Sn [37], Zn [38, 39], Mn [40] and Sc [41], have been *Correspondence: 1543046703@qq.com; oyl3074@163.com used for this coupling reaction which could afford the Xuzhou Medical University, Tongshan Road 209, Xuzhou 221004, China 2 corresponding homopropargyl alcohols. While, the by- School of Pharmaceutical Sciences, Gannan Medical University, Ganzhou 341000, China product allenyl alcohol is inevitable, which can be owned © The Author(s) 2022. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecom- mons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data. Zhang et al. BMC Chemistry (2022) 16:14 Page 2 of 9 to the rearrangement of the crucial intermediate progar- efficiency, good chemo-selectivity, and wide substrates gyl metal species to allenyl metal species [42]. Therefore, scopes under mild reaction conditions (Fig. 1). a mixture of homopropargyl alcohol and allenyl alcohol We initiated our investigation using benzaldehyde (1a) were generally obtained. Despite the encouraging pro- and propargyl bromide (2a) as model substrates which gress has been made [43–45], long reaction time–cost, catalyzed by copper salts and Mn powder (Table  1). moderate yields and low chemo-selectivity has limited Without Mn, only trace amount of desired product was the applications. Therefore, there is still demands for the observed which indicated that Mn powder is indispensa- improved method with respect to selectivities for homo- ble (Table 1, entry 1). While in the absence of C uBr , 16% propargyl alcohol and allenyl alcohols. of 3a was produced which demonstrated the great impor- As we known, Cu catalyst, is not only abundant, easy to tance of Cu catalyst (entry 2). Screening of different sol - utilize, and relatively insensitive to water and air, but also vents illustrated that MeCN is the best reaction medium, has advantageous for the controllable access to Cu(0), giving the desired product 3a in 47% yield (entry 3). Cu(I), Cu(II), and Cu(III) oxidation states [46, 47]; pos- While, only trace amount of product was observed in sibly because of its single-electron transfer (SET) and THF or DCM and 24% in EtOH (entries 4–6). The yield two-electron processes (TEPs) pathway [48, 49]; which of products dropped sharply when the reaction was car- make the catalytic system with high catalytic activities ried out in the open system (entry 7). Meanwhile, with- and rate. Moreover, Manganese has been widely used in out the addition of CF COOH, only 13% yield of 3a was organic reactions by virtue of its environmentally benign achieved (entry 8). Subsequently, extensive experiments and sustainable nature, low cost and versatile reactivity were conducted to investigate the effects of different cop - [50, 51]. Up to now, there were only few examples had per salts on the reaction. Series of Cu catalysts, including been reported, but they showed the activity of Mn in the CuSO , CuCl, CuCl , CuBr and CuI were tested and CuCl 4 2 proparylation reaction. So will the combination of Cu- gave the best result (entries 9–13). Adding 5 equiv. Mn catalyst and Mn powder increase the catalytic efficiency powder, a remarkable increase has been presented (entry in the proparylation of propargyl bromide with aldehyde? 14). Simultaneously, a light increase of yield was observed In this paper, we developed the first example of Cu-cat - by increasing the amount of catalyst (entry 15). Further alyzed and Mn-mediated propargylation and allenylation studies indicated that extending the reaction time to of aldehydes with propargyl bromides under a novel cat- 24  h, 1a can be transformed to 3a completely under the alytic system, which is covered with advantages of high standard conditions (entry 16). Fig. 1 Previous studies and our concept Zhang  et al. BMC Chemistry (2022) 16:14 Page 3 of 9 Table 1 The effect of different parameters on the reaction of 1a Table 2 Cu-catalyzed and Mn-mediated propargylation of a a and 2a.different aldehydes Entry [Cu] Solvent Mn Time/h Yield/% of 3a 1 CuBr MeCN – 12 Trace 2 – MeCN Mn 12 16 3 CuBr MeCN Mn 12 47 4 CuBr THF Mn 12 Trace 5 CuBr DCM Mn 12 Trace 6 CuBr EtOH Mn 12 24 7 CuBr MeCN Mn 12 24 8 CuBr MeCN Mn 12 13 9 CuSO MeCN Mn 12 59 10 CuCl MeCN Mn 12 83 11 CuCl MeCN Mn 12 63 12 CuBr MeCN Mn 12 74 13 CuI MeCN Mn 12 41 14 CuCl MeCN Mn 12 75 15 CuCl MeCN Mn 12 33 16 CuCl MeCN Mn 24 > 99 a Standard condition: a solution of 1 (0.5 mmol), 2a (1.5 equiv.), CuCl (10 mol%), Mn powder (3 equiv.) and CF COOH (0.25 equiv.) in MeCN (2.0 mL) was reacted Reaction conditions: All reactions were performed with 1a (0.5 mmol), 2a (1.5 conducted at room temperature under N atmosphere for 24 h equiv.), copper catalyst (10 mol%), Mn powder (3 equiv.), CF COOH (25 mol%), solvent (2 mL), at room temperature under N atmosphere. Yield was determined by GC with dodecane as internal standard based on 1a. Reaction in d e f the air. Without CF COOH. 5.0 equiv. of Mn was added. CuCl (20 mol%) was produced the homopropargyl alcohols in excellent yield. added. Naphthyl compounds is also effective for the transforma - tion converted to 3z and 3ab in the yield of 94% and 96% respectively. With the optimized setup in hand, we next explored the When 1-bromo-2-butyne (4a) was used instead of substrates scope of aldehydes with different functional propargyl bromide, the rearrangement product allenyl groups as shown in Table  2. It is pleasing that substrates alcohol was achieved with good yield under the same bearing both electron-donating groups (EDGs) and elec- reaction conditions (Table  3). Importantly, the direct tron-withdrawing groups (EWGs) can proceed smoothly. propargylation product was not detected in this cata- For example, substrates 3c, 3e, 3f, 3g, 3h, 3i, 3k and 3o lytic system, which indicated that the chemo-selectivity with alkyl and alkoxy groups can be transformed to the for this reaction is quite good. For example, substrates corresponding products in excellent yield. Substrates (5a–5c) which substituted by isopropyl-, methyl- and containing the halogen (3b, 3d, 3i, 3j) can also deliver the corresponding products with excellent yields. In addi- tion, disubstituted benzaldehydes, such as 2,4-dimethyl Table 3 Cu-catalyzed and Mn-mediated allenylation of different (3m), 2,3-dimethyl (3p), 2,5-difluoro (3n), 2,3-difluoro aldehydes (3o), 2-methoxy-4-methyl (3q) 3-chloro-5-fluoro (3r), 3-methoxy-4-fluoro (3s) and 3-methyl-4-fluor (3t) ben - zaldehydes were found to be compatible with the reac- tion in 85%- 95% yields. To further expand the scopes of the present catalytic system, reactions of heteroaromatic aldehydes including thiophenecarboxaldehyde (3v), pyri- dylaldehydes (3w and 3x) and quinolinecarboxaldehyde (3y) which contain aromatic heterocycle in the mol- Standard condition: a solution of 1 (0.5 mmol), 4a (1.5 equiv.), CuCl (10 mol%), ecules were also explored. Interesting, all of these sub- Mn powder (3 equiv.) and CF COOH (0.25 equiv.) in MeCN (2.0 mL) was reacted strates were compatible with the reaction conditions and conducted at room temperature under N atmosphere for 24 h 2 Zhang et al. BMC Chemistry (2022) 16:14 Page 4 of 9 fluoro- groups on the aromatic ring, reacted well and Based on the above results and studies reported in provided the corresponding products in moderate yields. the previous reference, a tentative mechanism for the In addition, heteroaromatic aldehyde (5d) is also worked Cu-Catalyzed, Mn-mediated propargylation and alle- for the transformation and an allenyl substituted alcohol nylation of aldehydes with propargyl bromides was (5e) was obtained with 85% yield. proposed in Fig.  3 [52–56]. Mn, which is severed as a I 0 To demonstrate the synthetic applications of our pro- strong reducing agent, reduced the Cu to Cu in an tocols, we tried to scale up the reaction of benzaldehyde active form in  situ. Insertion of C u to propargyl bro- (1a) with 3-bromo-1-propyne (2a) or 1-bromo-2-pentyne mides gives the crucial intermediate progargyl metal (4a) independently under standard conditions (Fig.  2). species (Int-I) and allenyl metal species (Int-II). Then, The corresponding products 3a or 5a was obtained in a nucleophilic addition of aldehydes conducted smoothly gram-scale, which highlightened the potential applicabil- with metal species to deliver the Int-III and Int-IV. ity of this transformation in organic synthesis. Finally, desired products were obtained in the presence Fig. 2 Gram-scale experiment Fig. 3 Proposed mechanism Zhang  et al. BMC Chemistry (2022) 16:14 Page 5 of 9 II 0 13 of CF COOH. The Cu complex was reduced to Cu 2.03 (s, 1H). C NMR (100 MHz, C DCl ) δ 139.6, 137.7, 3 3 with Mn powder to continue the next catalytic cycle. 129.2, 125.8, 80.9, 72.2, 70.9, 29.3, 21.2. In conclusion, the practical propargylation and alle- nylation of propargyl bromide has been discovered. The 1‑(4‑fluorophenyl)but‑3‑yn‑1‑ol (3d) [57] unique combination of the Cu catalyst and Mn pow- 97% yield (79.6  mg), colorless oil. H NMR (400  MHz, der present a novel and effective catalyst system in the CDCl ) δ 7.46–7.32 (m, 2H), 7.05 (t, J = 8.7  Hz, 2H), preparation of homopropargylation alcohols and allenyl 4.86 (t, J = 5.5  Hz, 1H), 2.62 (dd, J = 6.3, 2.6  Hz, 2H), alcohols. Wide substrates compatibility has been exhib- 2.49 (d, J = 2.5  Hz, 1H), 2.08 (t, J = 2.6  Hz, 1H). C ited with a variety of different substituent. This process NMR (100  MHz, CDCl ) δ 162.4 (d, J = 245  Hz), 138.2 represents a rare example of propargylation reaction and (d, J = 3 Hz), 127.5 d, J = 8 Hz), 115.4 (d, J = 21  Hz), 80.4, opens a new area of research. Further mechanistic stud- 71.7, 71.2, 29.6. ies and synthetic applications of this reaction are under progress in our laboratory. 1‑(4‑methoxyphenyl)but‑3‑yn‑1‑ol (3e) [57] 89% yield (78.4  mg), colorless oil. H NMR (400  MHz, Experiment CDCl ) δ 7.29 (d, J = 8.6 Hz, 2H), 6.95–6.80 (m, 2H), 4.80 Procedure for the synthesis of homopropargyl alcohol (t, J = 6.4  Hz, 1H), 3.79 (s, 3H), 2.64–2.58 (m, 2H), 2.05 In a 10 mL Schlenk tube, aldehyde (0.5 mmol) was added (t, J = 2.6  Hz, 1H). C NMR (100 MHz, CDCl ) δ 159.3, to a stirred solution of 3-bromo-1-propyne (1.5  eq.), 134.8, 127.1, 113.9, 80.9, 72.0, 70.9, 55.3, 29.3. CuCl (10  mol%), Mn powder (3.0  eq.), and CF COOH (25  mol%) in MeCN (2  mL) at room temperature under 1‑(4‑isopropylphenyl)but‑3‑yn‑1‑ol (3f ) [57] N atmosphere. After 24  h, the mixture was extracted 89% yield (83.7  mg), colorless oil. H NMR (400  MHz, with EtOAc (3 × 10 mL). The combined EtOAc layer was CDCl ) δ 7.30 (d, J = 8.1  Hz, 2H), 7.21 (d, J = 8.2  Hz, distilled and the crude product was then purified via col - 2H), 4.82 (s, 1H), 2.90 (dt, J = 13.8, 6.9 Hz, 1H), 2.62 (dd, umn chromatograph. J = 6.4, 2.6  Hz, 2H), 2.51 (s, 1H), 2.06 (t, J = 2.6  Hz, 1H), 1.24 (d, J = 6.9  Hz, 6H). C NMR (100  MHz, CDCl ) δ Procedure for the synthesis of allenyl alchols 148.7, 139.9, 126.6, 125.8, 81.0, 72.3, 70.9, 33.9, 29.3, 24.0. In a 10 mL Schlenk tube, aldehyde (0.5 mmol) was added to a stirred solution of 1-bromo-2-pentyne (1.5  eq.) 1‑(3‑methoxyphenyl)but‑3‑yn‑1‑ol (3g) [57] (1.5  eq.), CuCl (10  mol%), Mn powder (3.0  eq.), and 95% yield (83.6  mg), colorless oil. H NMR (400  MHz, CF COOH (25 mol%) in MeCN (2 mL) at room tempera- CDCl ) δ 7.27 (dd, J = 10.3, 5.9  Hz, 1H), 6.99–6.93 (m, 3 3 ture under N atmosphere. After 24  h, the mixture was 2H), 6.84 (ddd, J = 8.2, 2.5, 1.0 Hz, 1H), 4.85 (t, J = 6.3 Hz, extracted with EtOAc (3 × 10 mL). The combined EtOAc 1H), 3.81 (s, 3H), 2.69–2.59 (m, 2H), 2.51 (s, 1H), 2.08 layer was distilled and the crude product was then puri- (t, J = 2.6  Hz, 1H). C NMR (100 MHz, CDCl ) δ 159.7, fied via column chromatograph. 144.2, 129.6, 118.1, 113.5, 111.3, 80.7, 72.3, 71.0, 55.3, 29.4. 1‑phenylbut‑3‑yn‑1‑ol (3a) [57] 98% yield (71.6  mg), colourless oil. H NMR (400  MHz, 1‑(m‑tolyl)but‑3‑yn‑1‑ol (3h) [57] CDCl ) δ 7.46–7.34 (m, 4H), 7.30 (ddd, J = 8.5, 3.6, 83% yield (66.5  mg), colorless oil. H NMR (400  MHz, 1.6  Hz, 1H), 4.88 (t, J = 5.4  Hz, 1H), 2.71–2.56 (m, 2H), CDCl ) δ 7.24 (t, J = 7.5  Hz, 1H), 7.21–7.14 (m, 2H), 2.45 (s, 1H), 2.19–1.96 (m, 1H); C NMR (100  MHz, 7.10 (d, J = 7.4  Hz, 1H), 4.82 (t, J = 6.4  Hz, 1H), 2.62 CDCl ) δ 142.4, 128.5, 128.0, 125.8, 80.7, 72.3, 71.0, 29.5. (dd, J = 6.4, 2.6  Hz, 2H), 2.51 (s, 1H), 2.35 (s, 3H), 2.06 (t, J = 2.6  Hz, 1H). C NMR (100 MHz, CDCl ) δ 142.5, 1‑(4‑chlorophenyl)but‑3‑yn‑1‑ol (3b) [57] 138.2, 128.8, 128.4, 126.4, 122.9, 80.9, 72.4, 70.9, 29.4, 96% yield (86.7  mg), colorless oil. H NMR (400  MHz, 21.5. CDCl ) δ 7.33–7.25 (m, 4H), 4.80 (t, J = 5.1 Hz, 1H), 2.81 (s, 1H), 2.58 (dd, J = 6.4, 2.5  Hz, 2H), 2.06 (dd, J = 3.4, 1‑(2‑chlorophenyl)but‑3‑yn‑1‑ol (3i) [57] 13 1 1.7 Hz, 1H). C NMR (100 MHz, C DCl ) δ 140.9, 133.7, 96% yield (86.4  mg), colorless oil. H NMR (400  MHz, 128.6, 127.2, 80.3, 71.6, 71.4, 29.4. CDCl ) δ 7.62 (dd, J = 7.7, 1.4  Hz, 1H), 7.36–7.26 (m, 2H), 7.26–7.20 (m, 1H), 5.28 (dd, J = 7.8, 4.0  Hz, 1H), 1‑(p‑tolyl)but‑3‑yn‑1‑ol (3c) [57] 2.80 (ddd, J = 16.9, 3.9, 2.7  Hz, 1H), 2.69 (s, 1H), 2.54 91% yield (72.8  mg), colorless oil. H NMR (400  MHz, (ddd, J = 16.9, 7.8, 2.6  Hz, 1H), 2.10 (t, J = 2.6  Hz, 1H). CDCl ) δ 7.25 (d, J = 7.7 Hz, 2H), 7.14 (d, J = 7.7 Hz, 2H), C NMR (100 MHz, C DCl ) δ 139.7, 131.7, 129.4, 129.0, 3 3 4.79 (s, 1H), 2.58 (dd, J = 11.1, 8.7  Hz, 3H), 2.33 (s, 3H), 127.1, 127.1, 80.3, 71.2, 68.7, 27.7. Zhang et al. BMC Chemistry (2022) 16:14 Page 6 of 9 1‑(2‑fluorophenyl)but‑3‑yn‑1‑ol (3j) [57] 2.08 (t, J = 2.5  Hz , 1H). C NMR (100  MHz, CDCl ) δ 95% yield (79.9  mg), colorless oil. H NMR (400  MHz, 150.2 (dd, J = 246, 12 Hz), 147.6 (dd, J = 246, 13), 131.9 CDCl ) δ 7.52 (td, J = 7.5, 1.5 Hz, 1H), 7.26 (ddd, J = 7.1, (d, J = 10 Hz), 124.2 (dd, J = 7, 5 Hz), 121.8 (t, J = 3  Hz), 4.6, 1.9 Hz, 1H), 7.16 (td, J = 7.5, 0.8 Hz, 1H), 7.02 (ddd, 116.5 (d, J = 2 Hz), 79.8, 71.4, 66. 0 (t, J = 2 Hz), 28.2. J = 10.4, 8.2, 0.9  Hz, 1H), 5.18 (dd, J = 7.2, 4.9  Hz, 1H), 2.74 (ddd, J = 16.8, 4.7, 2.6 Hz, 1H), 2.62 (ddd, J = 16.8, 1‑(2,3‑dimethylphenyl)but‑3‑yn‑1‑ol (3p) [57] 7.6, 2.6  Hz, 2H), 2.07 (t, J = 2.6  Hz , 1H). C NMR 87% yield (75.7  mg), colorless oil. H NMR (400  MHz, (100 MHz, CDCl ) δ 160.0 (d, J = 244 Hz), 129.5, 129.3 CDCl ) δ 7.36 (d, J = 7.4  Hz, 1H), 7.17–7.04 (m, 2H), (d, J = 8  Hz), 127.2 (d, J = 4  Hz), 124.3 (d, J = 3  Hz), 3 5.15 (dd, J = 7.6, 5.0  Hz, 1H), 2.61–2.51 (m, 2H), 2.28 (s, 115.3 (d, J = 22 Hz), 80.3, 71.1, 66.4 (d, J = 2 Hz), 28.2. 3H), 2.22 (s, 3H), 2.07 (d, J = 2.4  Hz, 1H), 1.97 (s, 1H). C NMR (100 MHz, C DCl ) δ 140.4, 137.0, 133.2, 129.4, 1‑(4‑(trifluoromethyl)phenyl)but‑3‑yn‑1‑ol (3ak) [57] 1 125.8, 122.9, 81.2, 70.7, 69.3, 28.3, 20.7, 14.7. 75% yield (80.0  mg), colorless oil. H NMR (400  MHz, CDCl ) δ 7.60 (d, J = 8.2  Hz, 2H), 7.49 (d, J = 8.1  Hz , 2H), 4.90 (t, J = 6.3 Hz, 1H), 2.83 (s, 1H), 2.65 – 2.59 (m, 1‑(2‑methoxy‑4‑methylphenyl)but‑3‑yn‑1‑ol (3q) [57] 2H), 2.08 (s, 1H). C NMR (100 MHz, CDCl ) δ 146.3, 1 85% yield (80.8 mg), colorless oil. H NMR (400 MHz, 130.0 (q, J = 32 Hz), 126.1, 125.4 (q, J = 4 Hz), 123.9 (q, CDCl ) δ 7.25 (d, J = 7.6 Hz, 1H), 6.77 (d, J = 7.6 Hz, 1H), J = 270 Hz), 79.9, 71.6 (d, J = 7 Hz), 29.4. 6.68 (s, 1H), 5.09- 4.96 (m, 1H), 3.83 (d, J = 6.7 Hz, 3H), 2.98 (s, 1H), 2.67 (dddd, J = 24.2, 10.1, 6.3, 2.6 Hz, 2H), 1‑(4‑propoxyphenyl)but‑3‑yn‑1‑ol (3l) [57] 2.34 (s, 3H), 2.03 (t, J = 2.6 Hz, 1H). C NMR (100 MHz, 85% yield (86.8  mg), colorless oil. H NMR (400  MHz, CDCl ) δ 156.2, 138.9, 127.4, 126.8, 121.2, 111.4, 81.5, CDCl ) δ 7.30 (d, J = 8.5  Hz, 2H), 6.88 (d, J = 8.5  Hz , 70.4, 68.9, 55.2, 27.5, 21.6. 2H), 4.83 (t, J = 6.2  Hz, 1H), 3.91 (t, J = 6.6  Hz , 2H), 2.68–2.58 (m, 2H), 2.36 (s, 1H), 2.07 (d, J = 2.3  Hz , 1‑(3‑chloro‑5‑fluorophenyl)but‑3‑yn‑1‑ol (3r) [57] 1H), 1.80 (dd, J = 14.1, 7.0  Hz, 2H), 1.03 (t, J = 7.4  Hz , 95% yield (94.1  mg), colorless oil. H NMR (400  MHz, 3H). C NMR (100 MHz, C DCl ) δ 158.9, 134.4, 127.0, CDCl ) δ 7.19 (s, 1H), 7.07–6.99 (m, 2H), 4.84 (t, 114.4, 80.9, 72.1, 70.8, 69.5, 29.4, 22.6, 10.5. J = 4.6  Hz, 1H), 2.65–2.61 (m, 1H), 2.59 (dd, J = 6.5, 3.0  Hz, 1H), 2.11 (t, J = 2.6  Hz, 1H), 1.68 (s, 1H). C 1‑(2,4‑dimethylphenyl)but‑3‑yn‑1‑ol (3m) [57] NMR (100 MHz, CDCl ) δ 163.7 (d, J = 248 Hz), 146.2 (d, 85% yield (74.0  mg), colorless oil. H NMR (400  MHz, 3 J = 7  Hz), 135.1 (d, J = 10  Hz), 121.9 (d, J = 4  Hz), 115.6 CDCl ) δ 7.36 (d, J = 7.9  Hz, 1H), 7.03 (d, J = 7.7  Hz , (d, J = 25  Hz), 111.4 (d, J = 22  Hz), 79.6, 71.8, 71.2 (d, 1H), 6.95 (s, 1H), 5.04 (t, J = 6.4 Hz, 1H), 2.62–2.54 (m, J = 2 Hz), 29.4. 2H), 2.45 (d, J = 4.8  Hz, 1H), 2.30 (s, 3H), 2.29 (s, 3H), 2.05 (t, J = 2.6  Hz , 1H). C NMR (100  MHz, CDCl ) δ 137.6, 137.4, 134.6, 131.3, 127.0, 125.1, 81.1, 70.7, 68.8, 1‑(4‑fluoro‑3‑methoxyphenyl)but‑3‑yn‑1‑ol (3s) [57] 28.3, 21.0, 19.0. 88% yield (85.4  mg), colorless oil. H NMR (400  MHz, CDCl ) δ 7.09–7.01 (m, 2H), 6.88 (ddd, J = 8.3, 4.3, 1‑(2,5‑difluorophenyl)but‑3‑yn‑1‑ol (3n) [57] 2.1  Hz, 1H), 4.83 (t, J = 6.3  Hz, 1H), 3.89 (d, J = 5.9  Hz, 94% yield (85.6  mg), colorless oil. H NMR (400  MHz, 3H), 2.62 (dd, J = 6.4, 2.6  Hz, 2H), 2.55 (s, 1H), 2.09 (t, CDCl ) δ 7.26 (ddd, J = 8.8, 5.8, 3.0  Hz, 1H), 7.10–6.79 J = 2.6  Hz, 1H). C NMR (100 MHz, CDCl ) δ 151.914.7 (m, 2H), 5.24–5.07 (m, 1H), 2.83–2.48 (m, 3H), 2.10 (t, (d, J = 244  Hz), 147.6 (d, J = 11  Hz), 138.8 (d, J = 3  Hz), J = 2.6  Hz , 1H). C NMR (100  MHz, C DCl ) δ 158.9 118.1 (d, J = 7 Hz), 115.8 (d, J = 19 Hz), 110.9 (d, J = 2 Hz), (dd, J = 241, 2  Hz), 155.3 (dd, J = 238, 3  Hz), 131.2 (dd, 80.4, 71.9, 71.3, 56.2, 29.6. J = 16, 7  Hz), 116.3 (dd, J = 24, 8  Hz), 115.5 (dd, J = 24, 9  Hz), 113.9 (dd, J = 25, 4  Hz), 79.7, 71.6, 65.9, 28.2 (d, J = 1 Hz). 1‑(4‑fluoro‑3‑methylphenyl)but‑3‑yn‑1‑ol (3t) [57] 88% yield (78.4  mg), colorless oil. H NMR (400  MHz, CDCl ) δ 7.24–7.08 (m, 2H), 6.97 (t, J = 8.9  Hz, 1H), 1‑(2,3‑difluorophenyl)but‑3‑yn‑1‑ol (3o) [57] 4.81 (t, J = 6.3 Hz, 1H), 2.61 (dd, J = 6.3, 2.4 Hz, 2H), 2.45 87% yield (79.2  mg), colorless oil. H NMR (400  MHz, (s, 1H), 2.27 (s, 3H), 2.08 (s, 1H). C NMR (100  MHz, CDCl ) δ 7.33–7.23 (m, 1H), 7.18–7.01 (m, 2H), 5.19 CDCl ) δ 160.9 (d, J = 243 Hz), 137.87, 128.9 (d, J = 2 Hz), (dd, J = 6.9, 5.2 Hz, 1H), 2.82 (s, 1H), 2.74 (ddd, J = 16.8, 125.0, 124.7(d, J = 8  Hz), 114.9 (d, J = 22  Hz), 80.6, 71.8, 4.8, 2.6  Hz, 1H), 2.63 (ddd, J = 16.8, 7.4, 2.5  Hz, 1H), 71.1, 29.5, 14.7(d, J = 4 Hz). Zhang  et al. BMC Chemistry (2022) 16:14 Page 7 of 9 2‑(benzo[d][1,3]dioxol‑4‑yl)but‑3‑yn‑1‑ol (3u) [57] (d, J = 8.2 Hz, 1H), 7.69 (d, J = 7.2 Hz, 1H), 7.54–7.44 (m, 85% yield (80.8  mg), colorless oil. H NMR (400  MHz, 3H), 5.63 (dd, J = 8.2, 4.2 Hz, 1H), 2.87 (ddd, J = 17.0, 4.2, CDCl ) δ 6.95–6.89 (m, 1H), 6.84 (t, J = 7.8 Hz, 1H), 6.78 2.7  Hz, 1H), 2.73 (ddd, J = 17.0, 8.2, 2.6  Hz, 2H), 2.12 (t, (dd, J = 7.6, 1.0  Hz, 1H), 5.96 (dd, J = 9.2, 1.1  Hz, 2H), J = 2.6  Hz, 1H). C NMR (100  MHz, C DCl ) δ 137.8, 4.98 (dd, J = 10.2, 6.3  Hz, 1H), 2.84–2.58 (m, 3H), 2.06 133.8, 130.2, 129.1, 128.5, 126.3, 125.7, 125.4, 123.0, (t, J = 2.6  Hz, 1H). C NMR (100 MHz, CDCl ) δ 147.4, 122.8, 81.0, 71.3, 69.3, 28.7. 144.1, 124.1, 121.8, 119.3, 108.2, 101.0, 80.5, 70.9, 68.3, 27.6. 1‑(4‑isopropylphenyl)‑2‑methyl‑3λ5‑buta‑2,3‑dien‑1‑ol (5a) [57] 1‑(thiophen‑2‑yl)but‑3‑yn‑1‑ol (3v) [57] 76% yield (76.8  mg), colorless oil. H NMR (400  MHz, 88% yield (66.9  mg), colorless oil. H NMR (400  MHz, CDCl ) δ 7.30 (d, J = 8.0  Hz, 2H), 7.21 (d, J = 8.0  Hz, CDCl ) δ 7.32–7.22 (m, 1H), 6.99 (ddd, J = 11.1, 6.1, 2H), 5.07 (s, 1H), 4.96–4.85 (m, 2H), 2.90 (dt, J = 13.8, 2.5  Hz, 2H), 5.11 (d, J = 3.7  Hz, 1H), 2.79–2.68 (m, 6.9  Hz, 1H), 2.18 (s, 1H), 1.58 (t, J = 3.0  Hz, 3H), 1.24 3H), 2.11 (dd, J = 5.2, 2.6  Hz, 1H). C NMR (100  MHz, (d, J = 7.0  Hz, 6H). C NMR (100  MHz, CDCl ) δ 204.6, CDCl ) δ 146.2, 126.7, 125.0, 124.2, 80.1, 71.5, 68.5, 29.5. 148.6, 139.2, 126.6, 126.5, 102.7, 77. 9, 74.5, 33.9, 24.0, 14.7. 1‑(4‑chloropyridin‑2‑yl)but‑3‑yn‑1‑ol (3w) [57] 93% yield (84.1  mg), colorless oil. H NMR (400  MHz, CDCl ) δ 8.46 (d, J = 5.3  Hz, 1H), 7.49 (d, J = 1.7  Hz, 5 2‑methyl‑1‑(p‑tolyl)‑3λ ‑buta‑2,3‑dien‑1‑ol (5b) [57] 1H), 7.26 (dd, J = 5.4, 2.0 Hz, 1H), 4.88 (t, J = 6.0 Hz, 1H), 1 83% yield (54.9  mg), colorless oil. H NMR (400  MHz, 2.78–2.65 (m, 2H), 2.06 (t, J = 2.6  Hz, 1H), 1.25 (s, 1H). CDCl ) δ 7.25 (d, J = 8.0 Hz, 2H), 7.15 (d, J = 7.9 Hz, 2H), C NMR (100 MHz, C DCl ) δ 162.0, 149.4, 144.9, 123.3, 5.05 (s, 1H), 4.96–4.82 (m, 2H), 2.34 (s, 3H), 2.30 (s, 1H), 121.2, 80.0, 71.3, 71.1, 28.2. 13 1.56 (t, J = 3.1  Hz, 3H). C NMR (100  MHz, CDCl ) δ 204.7, 138.9, 137.5, 129.1, 126. 6, 102.7, 77.8, 74.5, 21.2, 1‑(pyridin‑3‑yl)but‑3‑yn‑1‑ol (3x) [57] 14.7. 95% yield (69.9  mg), colorless oil. H NMR (400  MHz, CDCl ) δ 8.54 (d, J = 2.0 Hz, 1H), 8.47 (dd, J = 4.8, 1.5 Hz, 1‑(4‑fluorophenyl)‑2‑methyl‑3λ ‑buta‑2,3‑dien‑1‑ol (5c) [57] 1H), 7.79 (dt, J = 7.9, 1.8 Hz, 1H), 7.33–7.26 (m, 1H), 4.92 73% yield (73  mg), colorless oil. H NMR (400  MHz, (t, J = 6.4 Hz, 1H), 2.70–2.65 (m, 2H), 2.08 (t, J = 2.6  Hz, CDCl ) δ 7.34 (dd, J = 8.4, 5.6 Hz, 2H), 7.03 (t, J = 8.7 Hz, 1H), 1.35–1.23 (m, 1H). C NMR (100  MHz, CDCl ) δ 2H), 5.08 (s, 1H), 4.93–4.86 (m, 2H), 2.39 (s, 1H), 1.55 (t, 148.9, 147.6, 138.3, 133.9, 123.5, 79.9, 71.5, 70.0, 29.3. J = 3.1  Hz, 3H). C NMR (100  MHz, CDCl ) δ 162.3(d, J = 244  Hz), 137.5 (d, J = 3  Hz), 128.3 (d, J = 8  Hz), 115.2 1‑(quinolin‑2‑yl)but‑3‑yn‑1‑ol (3y) [57] (d, J = 21 Hz), 102.6, 78.1, 77.4, 74.0, 14.5. 93% yield (92.0  mg), colorless oil. H NMR (400  MHz, CDCl ) δ 8.19 (d, J = 8.5 Hz, 1H), 8.09 (d, J = 8.5 Hz, 1H), 7.85 (d, J = 8.1  Hz, 1H), 7.73 (dd, J = 8.4, 1.4  Hz, 1H), 2‑methyl‑1‑(thiophen‑2‑yl)‑3λ ‑buta‑2,3‑dien‑1‑ol (5d) [57] 7.59–7.49 (m, 2H), 5.07 (t, J = 5.9  Hz, 1H), 2.80 (ddd, 76% yield (63.1  mg), colorless oil. H NMR (400  MHz, J = 5.9, 2.5, 1.7  Hz, 2H), 2.02 (t, J = 2.7  Hz, 1H), 1.25 (s, CDCl ) δ 7.29–7.25 (m, 1H), 7.02 (d, J = 3.1  Hz, 1H), 13 3 1H). C NMR (100  MHz, C DCl ) δ 160.0, 146.5, 137.0, 6.99–6.95 (m, 1H), 5.35 (s, 1H), 4.99–4.86 (m, 2H), 2.34 129.9, 128.9, 127.8, 127.7, 126.7, 118.5, 80.5, 71.0, 71.0, (d, J = 4.4  Hz, 1H), 1.69 (t, J = 3.0  Hz, 3H). C NMR 28.3. (100 MHz, CDCl ) δ 204.4, 146.1, 126.6, 125.2, 125.0, 102.6, 78.6, 70.7, 14.7. 1‑(naphthalen‑2‑yl)but‑3‑yn‑1‑ol (3z) [57] 94% yield (92.5  mg), colorless oil. H NMR (400  MHz, CDCl ) δ 7.87–7.70 (m, 4H), 7.56–7.36 (m, 3H), 4.98 Conclusions (t, J = 6.3  Hz, 1H), 2.75 (s, 1H), 2.69 (dd, J = 6.4, 2.6  Hz, In conclusion, we have established the first Cu-catalyzed, 2H), 2.05 (t, J = 2.6 Hz, 1H). C NMR (100 MHz, CDCl ) Mn-mediated propargylation and allenylation of alde- δ 139.9, 133.2, 133.2, 128.4, 128.1, 127.8, 126.3, 126.1, hydes with propargyl bromides. The unique combina - 124.8, 123.8, 80.8, 72.5, 71.2, 29.4. tion of the Cu catalyst and Mn powder present a novel and effective catalyst system in the preparation of homo - propargylation alcohols and allenyl alcohols. The overall 1‑(naphthalen‑1‑yl)but‑3‑yn‑1‑ol (3ab) [57] transformation is highly efficient with mild conditions, 96% yield (94.1  mg), colorless oil. H NMR (400  MHz, large substrate scope, and excellent chem-selectivity. CDCl ) δ 8.04 (d, J = 8.2 Hz, 1H), 7.89–7.83 (m, 1H), 7.79 3 Zhang et al. BMC Chemistry (2022) 16:14 Page 8 of 9 11. Zhang W, Ready JM. A concise total synthesis of dictyodendrins F, H, Supplementary Information and I using aryl ynol ethers as key building blocks. J Am Chem Soc. The online version contains supplementary material available at https:// doi. 2016;138:10684. org/ 10. 1186/ s13065- 022- 00803-3. 12. Praveen C, Ananth DB. Design, synthesis and cytotoxicity of pyrano[4,3-b] indol-1(5H)-ones: A hybrid pharmacophore approach via gold catalyzed Additional file 1. cyclization. Bioorg Med Chem Lett. 2016;26:2507. 13. Brasholz M, Reissig HU, Zimmer R. Sugars, alkaloids, and heteroaromat- ics: exploring heterocyclic chemistry with alkoxyallenes. Acc Chem Res. Acknowledgements 2009;42:45. Not applicable. 14. Urgoita G, San Martin R, Teresa Herrero M, Domínguez E. Aerobic cleav- age of alkenes and alkynes into carbonyl and carboxyl compounds. ACS Authors’ contributions Catal. 2017;7:3050. ZRL contributed to the conception of the study. XY and OL performed the 15. Chinchilla R, Nájera C. Chemicals from alkynes with palladium catalysts. experiment. ZRL and YYC contributed to analysis and manuscript preparation. Chem Rev. 2014;114:1783. All authors read and approved the final manuscript. 16. Lin W, Ma S. Enantioselective synthesis of naturally occurring isoquino- line alkaloids: (S)-(−)-trolline and (R)-(+)-oleracein E. Org Chem Front. Funding 2017;4:958. The authors thank the National Natural Science Foundation of China 17. Lu T, Lu Z, Ma ZX, Zhang Y, Hsung RP. Allenamides: A powerful and versa- (22161003) and the Project of Science and Technology of Xuzhou Govern- tile building block in organic synthesis. Chem Rev. 2013;113:4862. ment (No. KC16SG250). 18. Han Y, Ma S. Rhodium-catalyzed highly diastereoselective intramolecular [4 + 2] cycloaddition of 1,3-disubstituted allene-1,3-dienes. Org Chem Availability of data and materials Front. 2018;5:2680. All data generated or analyzed during this study are included in this published 19. Li QH, Jiang X, Wu K, Luo RQ, Liang M, Zhang ZH, Huang ZY. Research and its Additional file 1. progress on the catalytic enantioselective synthesis of axially chiral allenes by chiral organocatalysts. Curr Org Chem. 2020;24:694. 20. Shao XB, Zhang Z, Li QH, Zhao ZG. Synthesis of multi-substituted allenes Declarations from organoalane reagents and propargyl esters by using a nickel cata- lyst. Org Biomol Chem. 2018;16:4797. Ethics approval and consent to participate 21. Shao X, Wen C, Zhang G, Cao K, Wu L, Li QJ. Palladium-catalyzed, ligand- Not applicable. free SN ’ substitution reactions of organoaluminum with propargyl acetates for the synthesis of multi-substituted allenes. Organomet Chem. Consent for publication 2018;870:68. Not applicable. 22. Zhang Z, Shao XB, Zhang G, Li Q, Li X. Highly efficient synthesis of multi-substituted allenes from propargyl acetates and organoaluminum Competing interests reagents mediated by palladium. Synthesis. 2017;493:643. The authors declare no competing interests. 23. Zhang Z, Mo S, Zhang G, Shao X, Li Q, Zhong Y. Synthesis of multisubsti- tuted allenes via Palladium-catalyzed cross-coupling reaction of propar- Received: 15 November 2021 Accepted: 22 February 2022 gyl acetates with an organoaluminum reagent. Synlett. 2017;5:611. 24. Panek JS. Comprehensive organic synthesis. Oxford: Pergamon Press; 1991. p. 595. 25. Yamamoto H. Comprehensive organic synthesis. Oxford: Pergamon Press; 1991. p. 81. References 26. Yamaguchi M. Main group metals in organic synthesis. New York: Wiley- 1. Alami M, Hamze A, Provot O. Hydrostannation of alkynes. ACS Catal. VCH. Weinheim; 2004. p. 307. 2019;9:3437. 27. Smith MB, March J. March’s advanced organic chemistry: Reactions, 2. Parker KDJ, Fryzuk MD. Synthesis, structure, and reactivity of Niobium and mechanisms, and structure, 6th (Ed), Jon Wiley and Sons, Inc.: New York, Tantalum alkyne complexes. Organometallics. 2015;34:2037. 2006; 752. 3. Corpas J, Mauleón P, Gómez Arrayá M, Carretero JC. Transition-metal- 28. Yamamoto H. In Comprehensive organic synthesis. New York: Pergamon catalyzed functionalization of alkynes with organoboron reagents: new Press; 1991. p. 81. trends, mechanistic insights, and applications. ACS Catal. 2021;11:7513. 29. Isaac MB, Chan TH. Indium-mediated coupling of aldehydes with 4. Gilmore K, Alabugin IV. Cyclizations of Alkynes: Revisiting Baldwin’s rules prop-2-ynyl bromides in aqueous media. J Chem Soc Chem Commun. for ring closure. Chem Rev. 2011;111:6513. 1995;1003:89. 5. Liu L, Ward RM, Schomaker JM. Mechanistic aspects and synthetic appli- 30. Loh TP, Lin MJ, Tan KL. Indium-mediated propargylation of aldehydes: cations of radical additions to allenes. Chem Rev. 2019;119:12422. regioselectivity and enantioselectivity studies. Tetrahedron Lett. 6. Blieck R, Taillefer M, Monnier F. Metal-catalyzed intermolecular hydrofunc- 2003;44:507. tionalization of allenes: easy access to allylic structures via the selective 31. Haddad TD, Hirayama LC, Buckley JJ, Singaram BJ. Indium-mediated formation of C-N, C–C, and C–O Bonds. Chem Rev. 2020;120:13545. asymmetric Barbier-type propargylations: additions to aldehydes and 7. Zhai R, Xue Y, Liang T, Mi J, Xu Z. Regioselective arene and heteroarene ketones and mechanistic investigation of the organoindium reagents. functionalization: N-Alkenoxypyridinium salts as electrophilic alkylat- Org Chem. 2012;77:889. ing agents for the synthesis of α-aryl/α-heteroaryl ketones. J Org Chem. 32. Hojo M, Harada H, Ito H, Hosomi A. A new type of allyl- and prop-2-ynyl- 2018;83:10051. manganese species: generation and reactions with electrophiles. Chem 8. Baran PS, Shenvi RA. Total synthesis of (±)-Chartelline C. J Am Chem Soc. Commun. 1997;21:2077. 2006;128:14028. 33. Zha ZG, Hui AL, Zhou YQ, Miao Q, Wang ZY, Zhang HC. A Recyclable 9. Farahat AA, Kumar A, Say M, Barghash AEM, Goda FE, Eisa HM, Wenzler T, Electrochemical Allylation in Water. Org Lett. 2005;7:1903. Brun R, Liu Y, Mickelson L, Wilson WD, Boykin DW. Synthesis, DNA binding, 34. López-Martínez JL, Torres-García I, Rodríguez-García I, Muñoz-Dorado M, fluorescence measurements and antiparasitic activity of DAPI related Álvarez-Corral M. Stereoselective Barbier-Type allylations and propargyla- diamidines. Bioorg Med Chem. 2010;18:557. tions mediated by CpTiCl . J Org Chem. 2019;84:806. 10. Grover HK, Lebold TP, Kerr MA. Tandem Cyclopropane ring-opening/ 35. Hojo M, Sakuragi R, Okabe S, Hosomi A. Allyl- and propargylchromium Conia-ene reactions of 2-alkynyl indoles: A [3 + 3] annulative route to reagents generated by a chromium(III) ate-type reagent as a reductant tetrahydrocarbazoles. Org Lett. 2011;13:220. and their reactions with electrophiles. Chem Commun. 2001;357:8. Zhang  et al. BMC Chemistry (2022) 16:14 Page 9 of 9 36. Han Y, Chi Z, Huang YZ. Gallium-mediated highly regioselective reaction of allyl-type bromide and propargyl-type bromide with aldehyde. Synth Commun. 1999;29:1287. 37. Zha ZG, Qiao S, Jiang JY, Wang YS, Miao Q, Wang ZY. Barbier-type reaction mediated with tin nano-particles in water. Tetrahedron. 2005;61:2521. 38. Bieber LW, da Silva MF, da Costa RC, Silva LOS. Zinc barbier reaction of propargyl halides in water. Tetrahedron Lett. 1998;39:3655. 39. Fandrick DR, Reeves JT, Bakonyi J, Nyalapatla PR. Zinc catalyzed and mediated asymmetric propargylation of trifluoromethyl ketones with a propargyl boronate. J Org Chem. 2013;78:3592. 40. Iseki K, Kuroki Y, Kobayashi Y. Asymmetric allenylation of aliphatic aldehydes catalyzed by a chiral formamide. Tetrahedron Asymmetry. 1998;9:2889. 41. Evans DA, Sweeney ZK, Rovis T, Tedrow JS. Highly enantioselective syntheses of homopropargylic alcohols and dihydrofurans catalyzed by a bis(oxazolinyl)pyridine−Scandium triflate complex. J Am Chem Soc. 2001;123:12095. 42. Marshall JA, Gung BW, Grachan ML. Synthesis and reactions of alle- nylmetal compounds. In: Modern Allene Chemistry; (Ed.) Wiley-VCH: Weinheim, 2004; 493. 43. Thaima T, Zamani F, Hyland CJT, Pyne SG. Allenylation and propargylation reactions of ketones, aldehydes, imines, and iminium ions using organo- boronates and related derivatives. Synthesis. 2017;49:1461. 44. Denmark SD, Fu J. Catalytic enantioselective addition of allylic organome- tallic reagents to aldehydes and ketones. Chem Rev. 2003;103:2763. 45. Ma X, Li S, Devaramani S, Zhao G, Xu D. One-pot, regioselective synthesis of homopropargyl alcohols using propargyl bromide and carbonyl com- pound by the Mg-mediated reaction under solvent-free conditions. Lett Org Chem. 2020;17:438. 46. Wendlandt AE, Suess AM, Stahl SS. Copper-catalyzed aerobic oxidative C-H functionalizations: trends and mechanistic insights. Angew Chem Int Ed. 2011;50:11062. 47. McCann SD, Stahl SS. Copper-catalyzed aerobic oxidations of organic molecules: pathways for two-electron oxidation with a four-electron oxidant and a one-electron redox-active catalyst. Acc Chem Res. 2015;48:1756. 48. Allen SC, Walvoord RR, Padilla-Salinas R, Kozlowski MC. Aerobic copper- catalyzed organic reactions. Chem Rev. 2013;113:6234. 49. Guo XX, Gu DW, Wu Z, Zhang W. Copper-catalyzed C-H functionalization reactions: efficient synthesis of heterocycles. Chem Rev. 2015;115:1622. 50. Crossley SWM, Obradors C, Martinez RM, Shenvi RA. Mn-, Fe-, and Co-catalyzed radical hydrofunctionalizations of olefins. Chem Rev. 2016;116:8912. 51. Irrgang T, Kempe R. 3d-Metal catalyzed N- and C-alkylation reactions via borrowing hydrogen or hydrogen autotransfer. Chem Rev. 2019;119:2524. 52. Durandetti M, Périchon J. A simple practical method for the synthesis of 4,6-dimethoxy-1,3,5-triazin-2(1H)-one using dimethylamine-functional- ized solid-phase reagents. Synthesis. 2009;1:542. 53. Chattopadhyay A, Kr DA. A simple and efficient procedure of low valent iron- or copper-mediated reformatsky reaction of aldehydes. J Org Chem. 2007;72:9357. 54. Hojo M, Harada H, Cto H, Hosomi A. Manganese ate complexes as new reducing agents: perfectly regiocontrolled generation and reac- tions of the manganese enolates with electrophiles. J Am Chem Soc. 1997;119:5459. 55. Suh S, Rieke RD. Synthesis of β-hydroxy esters using highly active manga- nese. Tetrahedron Lett. 2004;45:1807. Re Read ady y to to submit y submit your our re researc search h ? Choose BMC and benefit fr ? Choose BMC and benefit from om: : 56. Liu XY, Li XR, Zhang R, Chu XQ, Rao W, Loh TP, Shen ZL. Iron(0)-mediated reformatsky reaction for the synthesis of β-hydroxyl carbonyl com- fast, convenient online submission pounds. Org Lett. 2019;21:5873. thorough peer review by experienced researchers in your field 57. Mori-Quiroz LM, Maloba EW, Maleczka RE. Silylcyclopropanes by selec- tive [1,4]-Wittig rearrangement of 4-silyl-5,6-dihydropyrans. Org Lett. rapid publication on acceptance 2021;23:5724. support for research data, including large and complex data types • gold Open Access which fosters wider collaboration and increased citations Publisher’s Note maximum visibility for your research: over 100M website views per year Springer Nature remains neutral with regard to jurisdictional claims in pub- lished maps and institutional affiliations. At BMC, research is always in progress. Learn more biomedcentral.com/submissions http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png BMC Chemistry Springer Journals

Cu-catalyzed, Mn-mediated propargylation and allenylation of aldehydes with propargyl bromides

BMC Chemistry , Volume 16 (1) – Mar 18, 2022

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Abstract

Introduction attracting a great deal of attentions [14–23]. Numerous Propargyl and allenyl groups are not only valuable build- methods have been established by using propargyl hal- ing blocks for further manipulations and organic trans- ides and metals to produce the nucleophilic character of formations in organic synthesis [1–7], but also sever as the propargyl metal species [24–26]. When the nucleo- active structural moieties in plentiful functional mol- philic receptor is an aldehyde, the homopropargyl alcohol ecules which are important in bioactive molecules, phar- can be obtained by the nucleophilic addition of propar- maceuticals agents and natural products [8–13]. Thus, gyl metal species and aldehyde [27, 28]. Variety of metals, this interesting and promising synthetic method has been including In [29–31], Sb [32], Pb [33], Ti [34], Cr [35], Ga [36], Sn [37], Zn [38, 39], Mn [40] and Sc [41], have been *Correspondence: 1543046703@qq.com; oyl3074@163.com used for this coupling reaction which could afford the Xuzhou Medical University, Tongshan Road 209, Xuzhou 221004, China 2 corresponding homopropargyl alcohols. While, the by- School of Pharmaceutical Sciences, Gannan Medical University, Ganzhou 341000, China product allenyl alcohol is inevitable, which can be owned © The Author(s) 2022. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecom- mons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data. Zhang et al. BMC Chemistry (2022) 16:14 Page 2 of 9 to the rearrangement of the crucial intermediate progar- efficiency, good chemo-selectivity, and wide substrates gyl metal species to allenyl metal species [42]. Therefore, scopes under mild reaction conditions (Fig. 1). a mixture of homopropargyl alcohol and allenyl alcohol We initiated our investigation using benzaldehyde (1a) were generally obtained. Despite the encouraging pro- and propargyl bromide (2a) as model substrates which gress has been made [43–45], long reaction time–cost, catalyzed by copper salts and Mn powder (Table  1). moderate yields and low chemo-selectivity has limited Without Mn, only trace amount of desired product was the applications. Therefore, there is still demands for the observed which indicated that Mn powder is indispensa- improved method with respect to selectivities for homo- ble (Table 1, entry 1). While in the absence of C uBr , 16% propargyl alcohol and allenyl alcohols. of 3a was produced which demonstrated the great impor- As we known, Cu catalyst, is not only abundant, easy to tance of Cu catalyst (entry 2). Screening of different sol - utilize, and relatively insensitive to water and air, but also vents illustrated that MeCN is the best reaction medium, has advantageous for the controllable access to Cu(0), giving the desired product 3a in 47% yield (entry 3). Cu(I), Cu(II), and Cu(III) oxidation states [46, 47]; pos- While, only trace amount of product was observed in sibly because of its single-electron transfer (SET) and THF or DCM and 24% in EtOH (entries 4–6). The yield two-electron processes (TEPs) pathway [48, 49]; which of products dropped sharply when the reaction was car- make the catalytic system with high catalytic activities ried out in the open system (entry 7). Meanwhile, with- and rate. Moreover, Manganese has been widely used in out the addition of CF COOH, only 13% yield of 3a was organic reactions by virtue of its environmentally benign achieved (entry 8). Subsequently, extensive experiments and sustainable nature, low cost and versatile reactivity were conducted to investigate the effects of different cop - [50, 51]. Up to now, there were only few examples had per salts on the reaction. Series of Cu catalysts, including been reported, but they showed the activity of Mn in the CuSO , CuCl, CuCl , CuBr and CuI were tested and CuCl 4 2 proparylation reaction. So will the combination of Cu- gave the best result (entries 9–13). Adding 5 equiv. Mn catalyst and Mn powder increase the catalytic efficiency powder, a remarkable increase has been presented (entry in the proparylation of propargyl bromide with aldehyde? 14). Simultaneously, a light increase of yield was observed In this paper, we developed the first example of Cu-cat - by increasing the amount of catalyst (entry 15). Further alyzed and Mn-mediated propargylation and allenylation studies indicated that extending the reaction time to of aldehydes with propargyl bromides under a novel cat- 24  h, 1a can be transformed to 3a completely under the alytic system, which is covered with advantages of high standard conditions (entry 16). Fig. 1 Previous studies and our concept Zhang  et al. BMC Chemistry (2022) 16:14 Page 3 of 9 Table 1 The effect of different parameters on the reaction of 1a Table 2 Cu-catalyzed and Mn-mediated propargylation of a a and 2a.different aldehydes Entry [Cu] Solvent Mn Time/h Yield/% of 3a 1 CuBr MeCN – 12 Trace 2 – MeCN Mn 12 16 3 CuBr MeCN Mn 12 47 4 CuBr THF Mn 12 Trace 5 CuBr DCM Mn 12 Trace 6 CuBr EtOH Mn 12 24 7 CuBr MeCN Mn 12 24 8 CuBr MeCN Mn 12 13 9 CuSO MeCN Mn 12 59 10 CuCl MeCN Mn 12 83 11 CuCl MeCN Mn 12 63 12 CuBr MeCN Mn 12 74 13 CuI MeCN Mn 12 41 14 CuCl MeCN Mn 12 75 15 CuCl MeCN Mn 12 33 16 CuCl MeCN Mn 24 > 99 a Standard condition: a solution of 1 (0.5 mmol), 2a (1.5 equiv.), CuCl (10 mol%), Mn powder (3 equiv.) and CF COOH (0.25 equiv.) in MeCN (2.0 mL) was reacted Reaction conditions: All reactions were performed with 1a (0.5 mmol), 2a (1.5 conducted at room temperature under N atmosphere for 24 h equiv.), copper catalyst (10 mol%), Mn powder (3 equiv.), CF COOH (25 mol%), solvent (2 mL), at room temperature under N atmosphere. Yield was determined by GC with dodecane as internal standard based on 1a. Reaction in d e f the air. Without CF COOH. 5.0 equiv. of Mn was added. CuCl (20 mol%) was produced the homopropargyl alcohols in excellent yield. added. Naphthyl compounds is also effective for the transforma - tion converted to 3z and 3ab in the yield of 94% and 96% respectively. With the optimized setup in hand, we next explored the When 1-bromo-2-butyne (4a) was used instead of substrates scope of aldehydes with different functional propargyl bromide, the rearrangement product allenyl groups as shown in Table  2. It is pleasing that substrates alcohol was achieved with good yield under the same bearing both electron-donating groups (EDGs) and elec- reaction conditions (Table  3). Importantly, the direct tron-withdrawing groups (EWGs) can proceed smoothly. propargylation product was not detected in this cata- For example, substrates 3c, 3e, 3f, 3g, 3h, 3i, 3k and 3o lytic system, which indicated that the chemo-selectivity with alkyl and alkoxy groups can be transformed to the for this reaction is quite good. For example, substrates corresponding products in excellent yield. Substrates (5a–5c) which substituted by isopropyl-, methyl- and containing the halogen (3b, 3d, 3i, 3j) can also deliver the corresponding products with excellent yields. In addi- tion, disubstituted benzaldehydes, such as 2,4-dimethyl Table 3 Cu-catalyzed and Mn-mediated allenylation of different (3m), 2,3-dimethyl (3p), 2,5-difluoro (3n), 2,3-difluoro aldehydes (3o), 2-methoxy-4-methyl (3q) 3-chloro-5-fluoro (3r), 3-methoxy-4-fluoro (3s) and 3-methyl-4-fluor (3t) ben - zaldehydes were found to be compatible with the reac- tion in 85%- 95% yields. To further expand the scopes of the present catalytic system, reactions of heteroaromatic aldehydes including thiophenecarboxaldehyde (3v), pyri- dylaldehydes (3w and 3x) and quinolinecarboxaldehyde (3y) which contain aromatic heterocycle in the mol- Standard condition: a solution of 1 (0.5 mmol), 4a (1.5 equiv.), CuCl (10 mol%), ecules were also explored. Interesting, all of these sub- Mn powder (3 equiv.) and CF COOH (0.25 equiv.) in MeCN (2.0 mL) was reacted strates were compatible with the reaction conditions and conducted at room temperature under N atmosphere for 24 h 2 Zhang et al. BMC Chemistry (2022) 16:14 Page 4 of 9 fluoro- groups on the aromatic ring, reacted well and Based on the above results and studies reported in provided the corresponding products in moderate yields. the previous reference, a tentative mechanism for the In addition, heteroaromatic aldehyde (5d) is also worked Cu-Catalyzed, Mn-mediated propargylation and alle- for the transformation and an allenyl substituted alcohol nylation of aldehydes with propargyl bromides was (5e) was obtained with 85% yield. proposed in Fig.  3 [52–56]. Mn, which is severed as a I 0 To demonstrate the synthetic applications of our pro- strong reducing agent, reduced the Cu to Cu in an tocols, we tried to scale up the reaction of benzaldehyde active form in  situ. Insertion of C u to propargyl bro- (1a) with 3-bromo-1-propyne (2a) or 1-bromo-2-pentyne mides gives the crucial intermediate progargyl metal (4a) independently under standard conditions (Fig.  2). species (Int-I) and allenyl metal species (Int-II). Then, The corresponding products 3a or 5a was obtained in a nucleophilic addition of aldehydes conducted smoothly gram-scale, which highlightened the potential applicabil- with metal species to deliver the Int-III and Int-IV. ity of this transformation in organic synthesis. Finally, desired products were obtained in the presence Fig. 2 Gram-scale experiment Fig. 3 Proposed mechanism Zhang  et al. BMC Chemistry (2022) 16:14 Page 5 of 9 II 0 13 of CF COOH. The Cu complex was reduced to Cu 2.03 (s, 1H). C NMR (100 MHz, C DCl ) δ 139.6, 137.7, 3 3 with Mn powder to continue the next catalytic cycle. 129.2, 125.8, 80.9, 72.2, 70.9, 29.3, 21.2. In conclusion, the practical propargylation and alle- nylation of propargyl bromide has been discovered. The 1‑(4‑fluorophenyl)but‑3‑yn‑1‑ol (3d) [57] unique combination of the Cu catalyst and Mn pow- 97% yield (79.6  mg), colorless oil. H NMR (400  MHz, der present a novel and effective catalyst system in the CDCl ) δ 7.46–7.32 (m, 2H), 7.05 (t, J = 8.7  Hz, 2H), preparation of homopropargylation alcohols and allenyl 4.86 (t, J = 5.5  Hz, 1H), 2.62 (dd, J = 6.3, 2.6  Hz, 2H), alcohols. Wide substrates compatibility has been exhib- 2.49 (d, J = 2.5  Hz, 1H), 2.08 (t, J = 2.6  Hz, 1H). C ited with a variety of different substituent. This process NMR (100  MHz, CDCl ) δ 162.4 (d, J = 245  Hz), 138.2 represents a rare example of propargylation reaction and (d, J = 3 Hz), 127.5 d, J = 8 Hz), 115.4 (d, J = 21  Hz), 80.4, opens a new area of research. Further mechanistic stud- 71.7, 71.2, 29.6. ies and synthetic applications of this reaction are under progress in our laboratory. 1‑(4‑methoxyphenyl)but‑3‑yn‑1‑ol (3e) [57] 89% yield (78.4  mg), colorless oil. H NMR (400  MHz, Experiment CDCl ) δ 7.29 (d, J = 8.6 Hz, 2H), 6.95–6.80 (m, 2H), 4.80 Procedure for the synthesis of homopropargyl alcohol (t, J = 6.4  Hz, 1H), 3.79 (s, 3H), 2.64–2.58 (m, 2H), 2.05 In a 10 mL Schlenk tube, aldehyde (0.5 mmol) was added (t, J = 2.6  Hz, 1H). C NMR (100 MHz, CDCl ) δ 159.3, to a stirred solution of 3-bromo-1-propyne (1.5  eq.), 134.8, 127.1, 113.9, 80.9, 72.0, 70.9, 55.3, 29.3. CuCl (10  mol%), Mn powder (3.0  eq.), and CF COOH (25  mol%) in MeCN (2  mL) at room temperature under 1‑(4‑isopropylphenyl)but‑3‑yn‑1‑ol (3f ) [57] N atmosphere. After 24  h, the mixture was extracted 89% yield (83.7  mg), colorless oil. H NMR (400  MHz, with EtOAc (3 × 10 mL). The combined EtOAc layer was CDCl ) δ 7.30 (d, J = 8.1  Hz, 2H), 7.21 (d, J = 8.2  Hz, distilled and the crude product was then purified via col - 2H), 4.82 (s, 1H), 2.90 (dt, J = 13.8, 6.9 Hz, 1H), 2.62 (dd, umn chromatograph. J = 6.4, 2.6  Hz, 2H), 2.51 (s, 1H), 2.06 (t, J = 2.6  Hz, 1H), 1.24 (d, J = 6.9  Hz, 6H). C NMR (100  MHz, CDCl ) δ Procedure for the synthesis of allenyl alchols 148.7, 139.9, 126.6, 125.8, 81.0, 72.3, 70.9, 33.9, 29.3, 24.0. In a 10 mL Schlenk tube, aldehyde (0.5 mmol) was added to a stirred solution of 1-bromo-2-pentyne (1.5  eq.) 1‑(3‑methoxyphenyl)but‑3‑yn‑1‑ol (3g) [57] (1.5  eq.), CuCl (10  mol%), Mn powder (3.0  eq.), and 95% yield (83.6  mg), colorless oil. H NMR (400  MHz, CF COOH (25 mol%) in MeCN (2 mL) at room tempera- CDCl ) δ 7.27 (dd, J = 10.3, 5.9  Hz, 1H), 6.99–6.93 (m, 3 3 ture under N atmosphere. After 24  h, the mixture was 2H), 6.84 (ddd, J = 8.2, 2.5, 1.0 Hz, 1H), 4.85 (t, J = 6.3 Hz, extracted with EtOAc (3 × 10 mL). The combined EtOAc 1H), 3.81 (s, 3H), 2.69–2.59 (m, 2H), 2.51 (s, 1H), 2.08 layer was distilled and the crude product was then puri- (t, J = 2.6  Hz, 1H). C NMR (100 MHz, CDCl ) δ 159.7, fied via column chromatograph. 144.2, 129.6, 118.1, 113.5, 111.3, 80.7, 72.3, 71.0, 55.3, 29.4. 1‑phenylbut‑3‑yn‑1‑ol (3a) [57] 98% yield (71.6  mg), colourless oil. H NMR (400  MHz, 1‑(m‑tolyl)but‑3‑yn‑1‑ol (3h) [57] CDCl ) δ 7.46–7.34 (m, 4H), 7.30 (ddd, J = 8.5, 3.6, 83% yield (66.5  mg), colorless oil. H NMR (400  MHz, 1.6  Hz, 1H), 4.88 (t, J = 5.4  Hz, 1H), 2.71–2.56 (m, 2H), CDCl ) δ 7.24 (t, J = 7.5  Hz, 1H), 7.21–7.14 (m, 2H), 2.45 (s, 1H), 2.19–1.96 (m, 1H); C NMR (100  MHz, 7.10 (d, J = 7.4  Hz, 1H), 4.82 (t, J = 6.4  Hz, 1H), 2.62 CDCl ) δ 142.4, 128.5, 128.0, 125.8, 80.7, 72.3, 71.0, 29.5. (dd, J = 6.4, 2.6  Hz, 2H), 2.51 (s, 1H), 2.35 (s, 3H), 2.06 (t, J = 2.6  Hz, 1H). C NMR (100 MHz, CDCl ) δ 142.5, 1‑(4‑chlorophenyl)but‑3‑yn‑1‑ol (3b) [57] 138.2, 128.8, 128.4, 126.4, 122.9, 80.9, 72.4, 70.9, 29.4, 96% yield (86.7  mg), colorless oil. H NMR (400  MHz, 21.5. CDCl ) δ 7.33–7.25 (m, 4H), 4.80 (t, J = 5.1 Hz, 1H), 2.81 (s, 1H), 2.58 (dd, J = 6.4, 2.5  Hz, 2H), 2.06 (dd, J = 3.4, 1‑(2‑chlorophenyl)but‑3‑yn‑1‑ol (3i) [57] 13 1 1.7 Hz, 1H). C NMR (100 MHz, C DCl ) δ 140.9, 133.7, 96% yield (86.4  mg), colorless oil. H NMR (400  MHz, 128.6, 127.2, 80.3, 71.6, 71.4, 29.4. CDCl ) δ 7.62 (dd, J = 7.7, 1.4  Hz, 1H), 7.36–7.26 (m, 2H), 7.26–7.20 (m, 1H), 5.28 (dd, J = 7.8, 4.0  Hz, 1H), 1‑(p‑tolyl)but‑3‑yn‑1‑ol (3c) [57] 2.80 (ddd, J = 16.9, 3.9, 2.7  Hz, 1H), 2.69 (s, 1H), 2.54 91% yield (72.8  mg), colorless oil. H NMR (400  MHz, (ddd, J = 16.9, 7.8, 2.6  Hz, 1H), 2.10 (t, J = 2.6  Hz, 1H). CDCl ) δ 7.25 (d, J = 7.7 Hz, 2H), 7.14 (d, J = 7.7 Hz, 2H), C NMR (100 MHz, C DCl ) δ 139.7, 131.7, 129.4, 129.0, 3 3 4.79 (s, 1H), 2.58 (dd, J = 11.1, 8.7  Hz, 3H), 2.33 (s, 3H), 127.1, 127.1, 80.3, 71.2, 68.7, 27.7. Zhang et al. BMC Chemistry (2022) 16:14 Page 6 of 9 1‑(2‑fluorophenyl)but‑3‑yn‑1‑ol (3j) [57] 2.08 (t, J = 2.5  Hz , 1H). C NMR (100  MHz, CDCl ) δ 95% yield (79.9  mg), colorless oil. H NMR (400  MHz, 150.2 (dd, J = 246, 12 Hz), 147.6 (dd, J = 246, 13), 131.9 CDCl ) δ 7.52 (td, J = 7.5, 1.5 Hz, 1H), 7.26 (ddd, J = 7.1, (d, J = 10 Hz), 124.2 (dd, J = 7, 5 Hz), 121.8 (t, J = 3  Hz), 4.6, 1.9 Hz, 1H), 7.16 (td, J = 7.5, 0.8 Hz, 1H), 7.02 (ddd, 116.5 (d, J = 2 Hz), 79.8, 71.4, 66. 0 (t, J = 2 Hz), 28.2. J = 10.4, 8.2, 0.9  Hz, 1H), 5.18 (dd, J = 7.2, 4.9  Hz, 1H), 2.74 (ddd, J = 16.8, 4.7, 2.6 Hz, 1H), 2.62 (ddd, J = 16.8, 1‑(2,3‑dimethylphenyl)but‑3‑yn‑1‑ol (3p) [57] 7.6, 2.6  Hz, 2H), 2.07 (t, J = 2.6  Hz , 1H). C NMR 87% yield (75.7  mg), colorless oil. H NMR (400  MHz, (100 MHz, CDCl ) δ 160.0 (d, J = 244 Hz), 129.5, 129.3 CDCl ) δ 7.36 (d, J = 7.4  Hz, 1H), 7.17–7.04 (m, 2H), (d, J = 8  Hz), 127.2 (d, J = 4  Hz), 124.3 (d, J = 3  Hz), 3 5.15 (dd, J = 7.6, 5.0  Hz, 1H), 2.61–2.51 (m, 2H), 2.28 (s, 115.3 (d, J = 22 Hz), 80.3, 71.1, 66.4 (d, J = 2 Hz), 28.2. 3H), 2.22 (s, 3H), 2.07 (d, J = 2.4  Hz, 1H), 1.97 (s, 1H). C NMR (100 MHz, C DCl ) δ 140.4, 137.0, 133.2, 129.4, 1‑(4‑(trifluoromethyl)phenyl)but‑3‑yn‑1‑ol (3ak) [57] 1 125.8, 122.9, 81.2, 70.7, 69.3, 28.3, 20.7, 14.7. 75% yield (80.0  mg), colorless oil. H NMR (400  MHz, CDCl ) δ 7.60 (d, J = 8.2  Hz, 2H), 7.49 (d, J = 8.1  Hz , 2H), 4.90 (t, J = 6.3 Hz, 1H), 2.83 (s, 1H), 2.65 – 2.59 (m, 1‑(2‑methoxy‑4‑methylphenyl)but‑3‑yn‑1‑ol (3q) [57] 2H), 2.08 (s, 1H). C NMR (100 MHz, CDCl ) δ 146.3, 1 85% yield (80.8 mg), colorless oil. H NMR (400 MHz, 130.0 (q, J = 32 Hz), 126.1, 125.4 (q, J = 4 Hz), 123.9 (q, CDCl ) δ 7.25 (d, J = 7.6 Hz, 1H), 6.77 (d, J = 7.6 Hz, 1H), J = 270 Hz), 79.9, 71.6 (d, J = 7 Hz), 29.4. 6.68 (s, 1H), 5.09- 4.96 (m, 1H), 3.83 (d, J = 6.7 Hz, 3H), 2.98 (s, 1H), 2.67 (dddd, J = 24.2, 10.1, 6.3, 2.6 Hz, 2H), 1‑(4‑propoxyphenyl)but‑3‑yn‑1‑ol (3l) [57] 2.34 (s, 3H), 2.03 (t, J = 2.6 Hz, 1H). C NMR (100 MHz, 85% yield (86.8  mg), colorless oil. H NMR (400  MHz, CDCl ) δ 156.2, 138.9, 127.4, 126.8, 121.2, 111.4, 81.5, CDCl ) δ 7.30 (d, J = 8.5  Hz, 2H), 6.88 (d, J = 8.5  Hz , 70.4, 68.9, 55.2, 27.5, 21.6. 2H), 4.83 (t, J = 6.2  Hz, 1H), 3.91 (t, J = 6.6  Hz , 2H), 2.68–2.58 (m, 2H), 2.36 (s, 1H), 2.07 (d, J = 2.3  Hz , 1‑(3‑chloro‑5‑fluorophenyl)but‑3‑yn‑1‑ol (3r) [57] 1H), 1.80 (dd, J = 14.1, 7.0  Hz, 2H), 1.03 (t, J = 7.4  Hz , 95% yield (94.1  mg), colorless oil. H NMR (400  MHz, 3H). C NMR (100 MHz, C DCl ) δ 158.9, 134.4, 127.0, CDCl ) δ 7.19 (s, 1H), 7.07–6.99 (m, 2H), 4.84 (t, 114.4, 80.9, 72.1, 70.8, 69.5, 29.4, 22.6, 10.5. J = 4.6  Hz, 1H), 2.65–2.61 (m, 1H), 2.59 (dd, J = 6.5, 3.0  Hz, 1H), 2.11 (t, J = 2.6  Hz, 1H), 1.68 (s, 1H). C 1‑(2,4‑dimethylphenyl)but‑3‑yn‑1‑ol (3m) [57] NMR (100 MHz, CDCl ) δ 163.7 (d, J = 248 Hz), 146.2 (d, 85% yield (74.0  mg), colorless oil. H NMR (400  MHz, 3 J = 7  Hz), 135.1 (d, J = 10  Hz), 121.9 (d, J = 4  Hz), 115.6 CDCl ) δ 7.36 (d, J = 7.9  Hz, 1H), 7.03 (d, J = 7.7  Hz , (d, J = 25  Hz), 111.4 (d, J = 22  Hz), 79.6, 71.8, 71.2 (d, 1H), 6.95 (s, 1H), 5.04 (t, J = 6.4 Hz, 1H), 2.62–2.54 (m, J = 2 Hz), 29.4. 2H), 2.45 (d, J = 4.8  Hz, 1H), 2.30 (s, 3H), 2.29 (s, 3H), 2.05 (t, J = 2.6  Hz , 1H). C NMR (100  MHz, CDCl ) δ 137.6, 137.4, 134.6, 131.3, 127.0, 125.1, 81.1, 70.7, 68.8, 1‑(4‑fluoro‑3‑methoxyphenyl)but‑3‑yn‑1‑ol (3s) [57] 28.3, 21.0, 19.0. 88% yield (85.4  mg), colorless oil. H NMR (400  MHz, CDCl ) δ 7.09–7.01 (m, 2H), 6.88 (ddd, J = 8.3, 4.3, 1‑(2,5‑difluorophenyl)but‑3‑yn‑1‑ol (3n) [57] 2.1  Hz, 1H), 4.83 (t, J = 6.3  Hz, 1H), 3.89 (d, J = 5.9  Hz, 94% yield (85.6  mg), colorless oil. H NMR (400  MHz, 3H), 2.62 (dd, J = 6.4, 2.6  Hz, 2H), 2.55 (s, 1H), 2.09 (t, CDCl ) δ 7.26 (ddd, J = 8.8, 5.8, 3.0  Hz, 1H), 7.10–6.79 J = 2.6  Hz, 1H). C NMR (100 MHz, CDCl ) δ 151.914.7 (m, 2H), 5.24–5.07 (m, 1H), 2.83–2.48 (m, 3H), 2.10 (t, (d, J = 244  Hz), 147.6 (d, J = 11  Hz), 138.8 (d, J = 3  Hz), J = 2.6  Hz , 1H). C NMR (100  MHz, C DCl ) δ 158.9 118.1 (d, J = 7 Hz), 115.8 (d, J = 19 Hz), 110.9 (d, J = 2 Hz), (dd, J = 241, 2  Hz), 155.3 (dd, J = 238, 3  Hz), 131.2 (dd, 80.4, 71.9, 71.3, 56.2, 29.6. J = 16, 7  Hz), 116.3 (dd, J = 24, 8  Hz), 115.5 (dd, J = 24, 9  Hz), 113.9 (dd, J = 25, 4  Hz), 79.7, 71.6, 65.9, 28.2 (d, J = 1 Hz). 1‑(4‑fluoro‑3‑methylphenyl)but‑3‑yn‑1‑ol (3t) [57] 88% yield (78.4  mg), colorless oil. H NMR (400  MHz, CDCl ) δ 7.24–7.08 (m, 2H), 6.97 (t, J = 8.9  Hz, 1H), 1‑(2,3‑difluorophenyl)but‑3‑yn‑1‑ol (3o) [57] 4.81 (t, J = 6.3 Hz, 1H), 2.61 (dd, J = 6.3, 2.4 Hz, 2H), 2.45 87% yield (79.2  mg), colorless oil. H NMR (400  MHz, (s, 1H), 2.27 (s, 3H), 2.08 (s, 1H). C NMR (100  MHz, CDCl ) δ 7.33–7.23 (m, 1H), 7.18–7.01 (m, 2H), 5.19 CDCl ) δ 160.9 (d, J = 243 Hz), 137.87, 128.9 (d, J = 2 Hz), (dd, J = 6.9, 5.2 Hz, 1H), 2.82 (s, 1H), 2.74 (ddd, J = 16.8, 125.0, 124.7(d, J = 8  Hz), 114.9 (d, J = 22  Hz), 80.6, 71.8, 4.8, 2.6  Hz, 1H), 2.63 (ddd, J = 16.8, 7.4, 2.5  Hz, 1H), 71.1, 29.5, 14.7(d, J = 4 Hz). Zhang  et al. BMC Chemistry (2022) 16:14 Page 7 of 9 2‑(benzo[d][1,3]dioxol‑4‑yl)but‑3‑yn‑1‑ol (3u) [57] (d, J = 8.2 Hz, 1H), 7.69 (d, J = 7.2 Hz, 1H), 7.54–7.44 (m, 85% yield (80.8  mg), colorless oil. H NMR (400  MHz, 3H), 5.63 (dd, J = 8.2, 4.2 Hz, 1H), 2.87 (ddd, J = 17.0, 4.2, CDCl ) δ 6.95–6.89 (m, 1H), 6.84 (t, J = 7.8 Hz, 1H), 6.78 2.7  Hz, 1H), 2.73 (ddd, J = 17.0, 8.2, 2.6  Hz, 2H), 2.12 (t, (dd, J = 7.6, 1.0  Hz, 1H), 5.96 (dd, J = 9.2, 1.1  Hz, 2H), J = 2.6  Hz, 1H). C NMR (100  MHz, C DCl ) δ 137.8, 4.98 (dd, J = 10.2, 6.3  Hz, 1H), 2.84–2.58 (m, 3H), 2.06 133.8, 130.2, 129.1, 128.5, 126.3, 125.7, 125.4, 123.0, (t, J = 2.6  Hz, 1H). C NMR (100 MHz, CDCl ) δ 147.4, 122.8, 81.0, 71.3, 69.3, 28.7. 144.1, 124.1, 121.8, 119.3, 108.2, 101.0, 80.5, 70.9, 68.3, 27.6. 1‑(4‑isopropylphenyl)‑2‑methyl‑3λ5‑buta‑2,3‑dien‑1‑ol (5a) [57] 1‑(thiophen‑2‑yl)but‑3‑yn‑1‑ol (3v) [57] 76% yield (76.8  mg), colorless oil. H NMR (400  MHz, 88% yield (66.9  mg), colorless oil. H NMR (400  MHz, CDCl ) δ 7.30 (d, J = 8.0  Hz, 2H), 7.21 (d, J = 8.0  Hz, CDCl ) δ 7.32–7.22 (m, 1H), 6.99 (ddd, J = 11.1, 6.1, 2H), 5.07 (s, 1H), 4.96–4.85 (m, 2H), 2.90 (dt, J = 13.8, 2.5  Hz, 2H), 5.11 (d, J = 3.7  Hz, 1H), 2.79–2.68 (m, 6.9  Hz, 1H), 2.18 (s, 1H), 1.58 (t, J = 3.0  Hz, 3H), 1.24 3H), 2.11 (dd, J = 5.2, 2.6  Hz, 1H). C NMR (100  MHz, (d, J = 7.0  Hz, 6H). C NMR (100  MHz, CDCl ) δ 204.6, CDCl ) δ 146.2, 126.7, 125.0, 124.2, 80.1, 71.5, 68.5, 29.5. 148.6, 139.2, 126.6, 126.5, 102.7, 77. 9, 74.5, 33.9, 24.0, 14.7. 1‑(4‑chloropyridin‑2‑yl)but‑3‑yn‑1‑ol (3w) [57] 93% yield (84.1  mg), colorless oil. H NMR (400  MHz, CDCl ) δ 8.46 (d, J = 5.3  Hz, 1H), 7.49 (d, J = 1.7  Hz, 5 2‑methyl‑1‑(p‑tolyl)‑3λ ‑buta‑2,3‑dien‑1‑ol (5b) [57] 1H), 7.26 (dd, J = 5.4, 2.0 Hz, 1H), 4.88 (t, J = 6.0 Hz, 1H), 1 83% yield (54.9  mg), colorless oil. H NMR (400  MHz, 2.78–2.65 (m, 2H), 2.06 (t, J = 2.6  Hz, 1H), 1.25 (s, 1H). CDCl ) δ 7.25 (d, J = 8.0 Hz, 2H), 7.15 (d, J = 7.9 Hz, 2H), C NMR (100 MHz, C DCl ) δ 162.0, 149.4, 144.9, 123.3, 5.05 (s, 1H), 4.96–4.82 (m, 2H), 2.34 (s, 3H), 2.30 (s, 1H), 121.2, 80.0, 71.3, 71.1, 28.2. 13 1.56 (t, J = 3.1  Hz, 3H). C NMR (100  MHz, CDCl ) δ 204.7, 138.9, 137.5, 129.1, 126. 6, 102.7, 77.8, 74.5, 21.2, 1‑(pyridin‑3‑yl)but‑3‑yn‑1‑ol (3x) [57] 14.7. 95% yield (69.9  mg), colorless oil. H NMR (400  MHz, CDCl ) δ 8.54 (d, J = 2.0 Hz, 1H), 8.47 (dd, J = 4.8, 1.5 Hz, 1‑(4‑fluorophenyl)‑2‑methyl‑3λ ‑buta‑2,3‑dien‑1‑ol (5c) [57] 1H), 7.79 (dt, J = 7.9, 1.8 Hz, 1H), 7.33–7.26 (m, 1H), 4.92 73% yield (73  mg), colorless oil. H NMR (400  MHz, (t, J = 6.4 Hz, 1H), 2.70–2.65 (m, 2H), 2.08 (t, J = 2.6  Hz, CDCl ) δ 7.34 (dd, J = 8.4, 5.6 Hz, 2H), 7.03 (t, J = 8.7 Hz, 1H), 1.35–1.23 (m, 1H). C NMR (100  MHz, CDCl ) δ 2H), 5.08 (s, 1H), 4.93–4.86 (m, 2H), 2.39 (s, 1H), 1.55 (t, 148.9, 147.6, 138.3, 133.9, 123.5, 79.9, 71.5, 70.0, 29.3. J = 3.1  Hz, 3H). C NMR (100  MHz, CDCl ) δ 162.3(d, J = 244  Hz), 137.5 (d, J = 3  Hz), 128.3 (d, J = 8  Hz), 115.2 1‑(quinolin‑2‑yl)but‑3‑yn‑1‑ol (3y) [57] (d, J = 21 Hz), 102.6, 78.1, 77.4, 74.0, 14.5. 93% yield (92.0  mg), colorless oil. H NMR (400  MHz, CDCl ) δ 8.19 (d, J = 8.5 Hz, 1H), 8.09 (d, J = 8.5 Hz, 1H), 7.85 (d, J = 8.1  Hz, 1H), 7.73 (dd, J = 8.4, 1.4  Hz, 1H), 2‑methyl‑1‑(thiophen‑2‑yl)‑3λ ‑buta‑2,3‑dien‑1‑ol (5d) [57] 7.59–7.49 (m, 2H), 5.07 (t, J = 5.9  Hz, 1H), 2.80 (ddd, 76% yield (63.1  mg), colorless oil. H NMR (400  MHz, J = 5.9, 2.5, 1.7  Hz, 2H), 2.02 (t, J = 2.7  Hz, 1H), 1.25 (s, CDCl ) δ 7.29–7.25 (m, 1H), 7.02 (d, J = 3.1  Hz, 1H), 13 3 1H). C NMR (100  MHz, C DCl ) δ 160.0, 146.5, 137.0, 6.99–6.95 (m, 1H), 5.35 (s, 1H), 4.99–4.86 (m, 2H), 2.34 129.9, 128.9, 127.8, 127.7, 126.7, 118.5, 80.5, 71.0, 71.0, (d, J = 4.4  Hz, 1H), 1.69 (t, J = 3.0  Hz, 3H). C NMR 28.3. (100 MHz, CDCl ) δ 204.4, 146.1, 126.6, 125.2, 125.0, 102.6, 78.6, 70.7, 14.7. 1‑(naphthalen‑2‑yl)but‑3‑yn‑1‑ol (3z) [57] 94% yield (92.5  mg), colorless oil. H NMR (400  MHz, CDCl ) δ 7.87–7.70 (m, 4H), 7.56–7.36 (m, 3H), 4.98 Conclusions (t, J = 6.3  Hz, 1H), 2.75 (s, 1H), 2.69 (dd, J = 6.4, 2.6  Hz, In conclusion, we have established the first Cu-catalyzed, 2H), 2.05 (t, J = 2.6 Hz, 1H). C NMR (100 MHz, CDCl ) Mn-mediated propargylation and allenylation of alde- δ 139.9, 133.2, 133.2, 128.4, 128.1, 127.8, 126.3, 126.1, hydes with propargyl bromides. The unique combina - 124.8, 123.8, 80.8, 72.5, 71.2, 29.4. tion of the Cu catalyst and Mn powder present a novel and effective catalyst system in the preparation of homo - propargylation alcohols and allenyl alcohols. The overall 1‑(naphthalen‑1‑yl)but‑3‑yn‑1‑ol (3ab) [57] transformation is highly efficient with mild conditions, 96% yield (94.1  mg), colorless oil. H NMR (400  MHz, large substrate scope, and excellent chem-selectivity. CDCl ) δ 8.04 (d, J = 8.2 Hz, 1H), 7.89–7.83 (m, 1H), 7.79 3 Zhang et al. BMC Chemistry (2022) 16:14 Page 8 of 9 11. Zhang W, Ready JM. A concise total synthesis of dictyodendrins F, H, Supplementary Information and I using aryl ynol ethers as key building blocks. J Am Chem Soc. The online version contains supplementary material available at https:// doi. 2016;138:10684. org/ 10. 1186/ s13065- 022- 00803-3. 12. Praveen C, Ananth DB. Design, synthesis and cytotoxicity of pyrano[4,3-b] indol-1(5H)-ones: A hybrid pharmacophore approach via gold catalyzed Additional file 1. cyclization. Bioorg Med Chem Lett. 2016;26:2507. 13. Brasholz M, Reissig HU, Zimmer R. Sugars, alkaloids, and heteroaromat- ics: exploring heterocyclic chemistry with alkoxyallenes. Acc Chem Res. Acknowledgements 2009;42:45. Not applicable. 14. Urgoita G, San Martin R, Teresa Herrero M, Domínguez E. Aerobic cleav- age of alkenes and alkynes into carbonyl and carboxyl compounds. ACS Authors’ contributions Catal. 2017;7:3050. ZRL contributed to the conception of the study. XY and OL performed the 15. Chinchilla R, Nájera C. Chemicals from alkynes with palladium catalysts. experiment. ZRL and YYC contributed to analysis and manuscript preparation. Chem Rev. 2014;114:1783. All authors read and approved the final manuscript. 16. Lin W, Ma S. Enantioselective synthesis of naturally occurring isoquino- line alkaloids: (S)-(−)-trolline and (R)-(+)-oleracein E. Org Chem Front. Funding 2017;4:958. The authors thank the National Natural Science Foundation of China 17. Lu T, Lu Z, Ma ZX, Zhang Y, Hsung RP. Allenamides: A powerful and versa- (22161003) and the Project of Science and Technology of Xuzhou Govern- tile building block in organic synthesis. Chem Rev. 2013;113:4862. ment (No. KC16SG250). 18. Han Y, Ma S. Rhodium-catalyzed highly diastereoselective intramolecular [4 + 2] cycloaddition of 1,3-disubstituted allene-1,3-dienes. Org Chem Availability of data and materials Front. 2018;5:2680. All data generated or analyzed during this study are included in this published 19. Li QH, Jiang X, Wu K, Luo RQ, Liang M, Zhang ZH, Huang ZY. Research and its Additional file 1. progress on the catalytic enantioselective synthesis of axially chiral allenes by chiral organocatalysts. Curr Org Chem. 2020;24:694. 20. Shao XB, Zhang Z, Li QH, Zhao ZG. Synthesis of multi-substituted allenes Declarations from organoalane reagents and propargyl esters by using a nickel cata- lyst. Org Biomol Chem. 2018;16:4797. Ethics approval and consent to participate 21. Shao X, Wen C, Zhang G, Cao K, Wu L, Li QJ. Palladium-catalyzed, ligand- Not applicable. free SN ’ substitution reactions of organoaluminum with propargyl acetates for the synthesis of multi-substituted allenes. Organomet Chem. Consent for publication 2018;870:68. Not applicable. 22. Zhang Z, Shao XB, Zhang G, Li Q, Li X. Highly efficient synthesis of multi-substituted allenes from propargyl acetates and organoaluminum Competing interests reagents mediated by palladium. Synthesis. 2017;493:643. The authors declare no competing interests. 23. Zhang Z, Mo S, Zhang G, Shao X, Li Q, Zhong Y. Synthesis of multisubsti- tuted allenes via Palladium-catalyzed cross-coupling reaction of propar- Received: 15 November 2021 Accepted: 22 February 2022 gyl acetates with an organoaluminum reagent. Synlett. 2017;5:611. 24. Panek JS. Comprehensive organic synthesis. Oxford: Pergamon Press; 1991. p. 595. 25. Yamamoto H. Comprehensive organic synthesis. Oxford: Pergamon Press; 1991. p. 81. References 26. Yamaguchi M. Main group metals in organic synthesis. New York: Wiley- 1. Alami M, Hamze A, Provot O. Hydrostannation of alkynes. ACS Catal. VCH. Weinheim; 2004. p. 307. 2019;9:3437. 27. Smith MB, March J. March’s advanced organic chemistry: Reactions, 2. Parker KDJ, Fryzuk MD. Synthesis, structure, and reactivity of Niobium and mechanisms, and structure, 6th (Ed), Jon Wiley and Sons, Inc.: New York, Tantalum alkyne complexes. Organometallics. 2015;34:2037. 2006; 752. 3. Corpas J, Mauleón P, Gómez Arrayá M, Carretero JC. Transition-metal- 28. Yamamoto H. In Comprehensive organic synthesis. New York: Pergamon catalyzed functionalization of alkynes with organoboron reagents: new Press; 1991. p. 81. trends, mechanistic insights, and applications. ACS Catal. 2021;11:7513. 29. Isaac MB, Chan TH. Indium-mediated coupling of aldehydes with 4. Gilmore K, Alabugin IV. Cyclizations of Alkynes: Revisiting Baldwin’s rules prop-2-ynyl bromides in aqueous media. J Chem Soc Chem Commun. for ring closure. Chem Rev. 2011;111:6513. 1995;1003:89. 5. Liu L, Ward RM, Schomaker JM. Mechanistic aspects and synthetic appli- 30. Loh TP, Lin MJ, Tan KL. Indium-mediated propargylation of aldehydes: cations of radical additions to allenes. Chem Rev. 2019;119:12422. regioselectivity and enantioselectivity studies. Tetrahedron Lett. 6. Blieck R, Taillefer M, Monnier F. Metal-catalyzed intermolecular hydrofunc- 2003;44:507. tionalization of allenes: easy access to allylic structures via the selective 31. Haddad TD, Hirayama LC, Buckley JJ, Singaram BJ. Indium-mediated formation of C-N, C–C, and C–O Bonds. Chem Rev. 2020;120:13545. asymmetric Barbier-type propargylations: additions to aldehydes and 7. Zhai R, Xue Y, Liang T, Mi J, Xu Z. Regioselective arene and heteroarene ketones and mechanistic investigation of the organoindium reagents. functionalization: N-Alkenoxypyridinium salts as electrophilic alkylat- Org Chem. 2012;77:889. ing agents for the synthesis of α-aryl/α-heteroaryl ketones. J Org Chem. 32. Hojo M, Harada H, Ito H, Hosomi A. A new type of allyl- and prop-2-ynyl- 2018;83:10051. manganese species: generation and reactions with electrophiles. Chem 8. Baran PS, Shenvi RA. Total synthesis of (±)-Chartelline C. J Am Chem Soc. Commun. 1997;21:2077. 2006;128:14028. 33. Zha ZG, Hui AL, Zhou YQ, Miao Q, Wang ZY, Zhang HC. A Recyclable 9. Farahat AA, Kumar A, Say M, Barghash AEM, Goda FE, Eisa HM, Wenzler T, Electrochemical Allylation in Water. Org Lett. 2005;7:1903. Brun R, Liu Y, Mickelson L, Wilson WD, Boykin DW. Synthesis, DNA binding, 34. López-Martínez JL, Torres-García I, Rodríguez-García I, Muñoz-Dorado M, fluorescence measurements and antiparasitic activity of DAPI related Álvarez-Corral M. Stereoselective Barbier-Type allylations and propargyla- diamidines. Bioorg Med Chem. 2010;18:557. tions mediated by CpTiCl . J Org Chem. 2019;84:806. 10. Grover HK, Lebold TP, Kerr MA. Tandem Cyclopropane ring-opening/ 35. Hojo M, Sakuragi R, Okabe S, Hosomi A. Allyl- and propargylchromium Conia-ene reactions of 2-alkynyl indoles: A [3 + 3] annulative route to reagents generated by a chromium(III) ate-type reagent as a reductant tetrahydrocarbazoles. Org Lett. 2011;13:220. and their reactions with electrophiles. Chem Commun. 2001;357:8. Zhang  et al. BMC Chemistry (2022) 16:14 Page 9 of 9 36. Han Y, Chi Z, Huang YZ. Gallium-mediated highly regioselective reaction of allyl-type bromide and propargyl-type bromide with aldehyde. Synth Commun. 1999;29:1287. 37. Zha ZG, Qiao S, Jiang JY, Wang YS, Miao Q, Wang ZY. Barbier-type reaction mediated with tin nano-particles in water. Tetrahedron. 2005;61:2521. 38. Bieber LW, da Silva MF, da Costa RC, Silva LOS. Zinc barbier reaction of propargyl halides in water. Tetrahedron Lett. 1998;39:3655. 39. Fandrick DR, Reeves JT, Bakonyi J, Nyalapatla PR. Zinc catalyzed and mediated asymmetric propargylation of trifluoromethyl ketones with a propargyl boronate. J Org Chem. 2013;78:3592. 40. Iseki K, Kuroki Y, Kobayashi Y. Asymmetric allenylation of aliphatic aldehydes catalyzed by a chiral formamide. Tetrahedron Asymmetry. 1998;9:2889. 41. Evans DA, Sweeney ZK, Rovis T, Tedrow JS. Highly enantioselective syntheses of homopropargylic alcohols and dihydrofurans catalyzed by a bis(oxazolinyl)pyridine−Scandium triflate complex. J Am Chem Soc. 2001;123:12095. 42. Marshall JA, Gung BW, Grachan ML. Synthesis and reactions of alle- nylmetal compounds. In: Modern Allene Chemistry; (Ed.) Wiley-VCH: Weinheim, 2004; 493. 43. Thaima T, Zamani F, Hyland CJT, Pyne SG. Allenylation and propargylation reactions of ketones, aldehydes, imines, and iminium ions using organo- boronates and related derivatives. Synthesis. 2017;49:1461. 44. Denmark SD, Fu J. Catalytic enantioselective addition of allylic organome- tallic reagents to aldehydes and ketones. Chem Rev. 2003;103:2763. 45. Ma X, Li S, Devaramani S, Zhao G, Xu D. One-pot, regioselective synthesis of homopropargyl alcohols using propargyl bromide and carbonyl com- pound by the Mg-mediated reaction under solvent-free conditions. Lett Org Chem. 2020;17:438. 46. Wendlandt AE, Suess AM, Stahl SS. Copper-catalyzed aerobic oxidative C-H functionalizations: trends and mechanistic insights. Angew Chem Int Ed. 2011;50:11062. 47. McCann SD, Stahl SS. Copper-catalyzed aerobic oxidations of organic molecules: pathways for two-electron oxidation with a four-electron oxidant and a one-electron redox-active catalyst. Acc Chem Res. 2015;48:1756. 48. Allen SC, Walvoord RR, Padilla-Salinas R, Kozlowski MC. Aerobic copper- catalyzed organic reactions. Chem Rev. 2013;113:6234. 49. Guo XX, Gu DW, Wu Z, Zhang W. Copper-catalyzed C-H functionalization reactions: efficient synthesis of heterocycles. Chem Rev. 2015;115:1622. 50. Crossley SWM, Obradors C, Martinez RM, Shenvi RA. Mn-, Fe-, and Co-catalyzed radical hydrofunctionalizations of olefins. Chem Rev. 2016;116:8912. 51. Irrgang T, Kempe R. 3d-Metal catalyzed N- and C-alkylation reactions via borrowing hydrogen or hydrogen autotransfer. Chem Rev. 2019;119:2524. 52. Durandetti M, Périchon J. A simple practical method for the synthesis of 4,6-dimethoxy-1,3,5-triazin-2(1H)-one using dimethylamine-functional- ized solid-phase reagents. Synthesis. 2009;1:542. 53. Chattopadhyay A, Kr DA. A simple and efficient procedure of low valent iron- or copper-mediated reformatsky reaction of aldehydes. J Org Chem. 2007;72:9357. 54. Hojo M, Harada H, Cto H, Hosomi A. Manganese ate complexes as new reducing agents: perfectly regiocontrolled generation and reac- tions of the manganese enolates with electrophiles. J Am Chem Soc. 1997;119:5459. 55. Suh S, Rieke RD. Synthesis of β-hydroxy esters using highly active manga- nese. Tetrahedron Lett. 2004;45:1807. Re Read ady y to to submit y submit your our re researc search h ? Choose BMC and benefit fr ? Choose BMC and benefit from om: : 56. Liu XY, Li XR, Zhang R, Chu XQ, Rao W, Loh TP, Shen ZL. Iron(0)-mediated reformatsky reaction for the synthesis of β-hydroxyl carbonyl com- fast, convenient online submission pounds. Org Lett. 2019;21:5873. thorough peer review by experienced researchers in your field 57. Mori-Quiroz LM, Maloba EW, Maleczka RE. Silylcyclopropanes by selec- tive [1,4]-Wittig rearrangement of 4-silyl-5,6-dihydropyrans. Org Lett. rapid publication on acceptance 2021;23:5724. support for research data, including large and complex data types • gold Open Access which fosters wider collaboration and increased citations Publisher’s Note maximum visibility for your research: over 100M website views per year Springer Nature remains neutral with regard to jurisdictional claims in pub- lished maps and institutional affiliations. At BMC, research is always in progress. Learn more biomedcentral.com/submissions

Journal

BMC ChemistrySpringer Journals

Published: Mar 18, 2022

Keywords: Propargylation; Allenylation; Mn powder; Cu-catalyzed; Gram scale

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