Copper‐Catalysed Synthesis of Propargyl Alcohol and Derivatives from Acetylene and other Terminal Alkynes

Abstract

A copper(I)/phosphine system that homogeneously catalyses the alkynylation of formaldehyde with acetylene or terminal alkynes is reported. Using acetylene at atmospheric pressure, the catalyst consisting of < 1 mol% copper(I) phenylacetylide and a trialkyl bisphosphine ligand shows a high selectivity towards the formation of propargyl alcohol rather than 1,4-butynediol, which is not reported for common heterogeneous copper acetylide catalysts. The biphasic water/toluene reaction mixture allows the separation of targeted products with the aqueous layer and catalyst recycling via the organic layer.

The importance of copper-phyllosilicate formed in CuO/SiO2 catalysts in the ethynylation of formaldehyde for 1,4-butynediol synthesis

“…Cu-based catalysts have been applied in the ethynylation of formaldehyde for the synthesis of 1,4-butynediol, which is named as the Reppe method. 9,10 Cu + or Cu 2 C 2 formed in situ have been considered as active centers known from the ethynylation reaction mechanism reported. 11,12 However, Cu 0 derived from Cu + or Cu 2+ by reduction are not favourable because Cu 0 may induce the formation of byproduct polyacetylene and active centers may be covered.…”

Ligand Control of Copper-Mediated Cycloadditions of Acetylene to Azides: Chemo- and Regio-Selective Formation of Deutero- and Iodo-Substituted 1,2,3-Triazoles

“…Acetylene is an important industrial feedstock in the production of organic chemicals . As a readily available source, acetylene or its precursor CaC 2 has received great attention as a C2 building block in a variety of pathways for the synthesis of organic substances. − To date, large number of transformations of this gas have been developed, which take advantage of its diverse reactivity profile to create a variety of unique structures. − Importantly, these studies have led to the discovery of a wide range of synthetically useful copper­(I)-catalyzed transformations − ,, such as alkylations, cycloadditions, coupling, − , and cascade reactions . The mechanistic routes proposed for these reactions involve the intermediacy of π-acetylene and σ-acetylide complexes, and in some cases, the intermediate Cu­(I) π-acetylene have been isolated and characterized .…”

Base-catalyzed addition of silylacetylenes to ketones: a route to protected tertiary propargyl alcohols

“…26 Here, besides stoichiometric approaches, several catalytic protocols were developed as well. 27–37…”

“…26 Here, besides stoichiometric approaches, several catalytic protocols were developed as well. [27][28][29][30][31][32][33][34][35][36][37] The application of Earth-abundant species as catalysts have gained recent significant attention in organic chemistry. [38][39][40][41][42][43][44][45][46][47][48][49] Considering our recent success in activating organometalloids under sustainable catalysis, [50][51][52][53][54][55][56] we reasoned that an appropriate catalytic manifold could provide an efficient platform to generate diversified libraries of protected propargyl alcohols.…”