Reaction mechanism of copper(I) catalysed head-to-head dimerization of 1-alkynes : an experimental and theoretical study

Effect of Varying the Anionic Component of a Copper(I) Catalyst on Homologation of Arylacetylenes to Allenes by the Mannich Reaction

“…In studies carried out by Bohlmann et al [15] on the rate of dimerization as influenced by the electronic nature of conjugated acetylenes, they found that more acidic acetylenes underwent more rapid dimerization under alkaline conditions, which was consistent with results obtained by Klebansky et al [16] However, under acidic conditions, an inverse relationship was observed, and addition of a copper(I) salt became necessary. This is also in a agreement with the recent results obtained by Balcioglu et al [17] Scheme 2. Mechanism of allene formation in CuBr-catalyzed reactions.…”

Acetylenic Coupling: A Powerful Tool in Molecular Construction

“…[192,193] In these systems the buta-1,3- 43a X = CH 2 CH 2 OCH 2 CH 2 43b X = CH 2 CH 2 CH 3 + + Scheme 39. The buta-1,3-diynediyl-linked macrotricyclic receptor (AE)-46 (Scheme 40) was synthesized in our research group with the aim of providing a deep cavity capable of incorporating both the tetracyclic A ± D ring system of steroids and parts of the isoprenoidal side chain at C (17). [192,193] Angew.…”

Selective Dimerization of Arylalkynes to (E)-1,4-Diaryl Enynes Catalyzed by the [Ru(p-cymene)Cl2]2/Acetic Acid System under Phosphine-Free Conditions

“…Active catalytic systems for this reaction are found in main group elements, rare-earth, or transition metal complexes 6a while appropriate additives can shift the selectivity toward 1,4-disubstitution .…”