α-Alkynols 1 are converted in high yield and selectivity into conjugatedenynes 2 or α,β-unsaturatedketones 3 by treatment with acid zeolites. The exclusive production of compounds 2 or 3 depends on the nature of the starting material 1 and experimental conditions.
Copper-Catalyzed Regioselective and Stereoselective Coupling of Grignard Reagents with Pent-1-en-4-yn-3-yl Benzoates: A Shortcut to (<i>Z</i>)<i>-</i>1,5-Disubstituted Pent-3-en-1-ynes from Accessible Starting Materials
Copper-catalyzed coupling of Grignardreagents with pent-1-en-4-yn-3-yl benzoates occurs regioselectively at the terminal alkenyl carbon rather than the alkynyl site, leading to the stereoselective formation of unexpected (Z)-1,5-disubstituted pent-3-en-1-ynes without generation of the initially expected alkenyl allene products. By using easily accessible starting materials, this reaction can provide
Selective linearcodimerization of terminal acetylenes and buta-1,3-diene catalysed by the first example of a dihydridotetrakis(trialkylphosphine)-ruthenium complex is reported.
Organocuprate-induced coupling of propargyl or enyne alcohols using (methylphenylamino)tributylphosphonium iodide. Regiocontrolled synthesis of allenes and conjugated enynes