One-pot, solvent-free regioselective addition reactions of propargyl bromide to carbonyl compounds mediated by Zn–Cu couple

Highly Efficient Synthesis of 5‐Substituted 1H‐Tetrazoles Catalyzed by Cu–Zn Alloy Nanopowder, Conversion into 1,5‐ and 2,5‐Disubstituted Tetrazoles, and Synthesis and NMR Studies of New Tetrazolium Ionic Liquids

“…Although copper‐ and zinc‐based molecular catalysts have been employed for decades in a wide variety of organic transformations, there has been intense recent research interest in their more efficient application in the nanoparticulate forms 11,13. The utility of bimetallic catalysts has been demonstrated in important transformations such as Ullmann reactions (Cu–Zn nanocatalyst),14 propargylation of ketones (Cu–Zn couple),15 industrial methanol synthesis (ZnO supported Cu),16 and in certain cross‐coupling reactions (Cu–Ni–C) 17. The potential for synergic effects between two metals led us to explore the efficacy of bimetallic Cu–Zn nanoparticles in [3+2] cycloaddition reactions between nitriles and azides for the construction of 5‐substituted 1 H ‐tetrazoles.…”

Skeletal Diversification via Heteroatom Linkage Control: Preparation of Bicyclic and Spirocyclic Scaffolds from N-Substituted Homopropargyl Alcohols

“…A more direct method using 1 , propargyl bromide and Zn/Cu couple with sonication afforded 3 accompanied by a minor amount of its inseparable allene isomer (not shown). 8 The allene byproduct did not introduce any apparent complications in the subsequent steps. Treatment of 3 with ICl afforded, not the anticipated 4 , but the bicyclic [3.2.1] β-iodo-enamine HCl salt 5a after extraction and lyophilization.…”

“…(CAUTION: This reaction can be accompanied by a vigorous exotherm and should be properly cooled and vented). Using a procedure modified from that of Wang, 8 to a solution of N -Boc-3-piperidone (10.13 g, 50.80 mmol) and propargyl bromide (8.49 mL of an 80 wt% solution in toluene, 76.00 mmol) in THF (10.2 mL) at 0 °C was added Zn/Cu couple (4.550 g, 55.90 mmol). The mixture was sonicated for 10 min then diluted with sat’d aqueous NH 4 Cl and ethyl acetate.…”

Synthesis and evaluation of β-hydroxytriazoles and related compounds as antitubercular agents

“…(1f, 41%) [22], 1-(4-chloropheny)but-3-yn-1-ol (1h, 75%) [20], 1-(2-chloropheny)but-3-yn-1-ol (1i, 24%) [20], 1-(2,6-dichlorophenyl)but-3-yn-1-ol (1j, 74%) [23], 1-(2,4-dichlorophenyl)but-3-yn-1-ol (1k, 88%) [20], 1-(4-fluorophenyl)but-3-yn-1-ol (1t, 23%) [21], 1-(4-bromophenyl)but-3-yn-1-ol (1u, 78%) [23]. The synthesized products were used as such for the next reaction (presence of α-allenol <5-10% by 1 H NMR).…”