Using Pd-Salen Complex as an Efficient Catalyst for the Copper- and Solvent-Free Coupling of Acyl Chlorides with Terminal Alkynes under Aerobic Conditions.

Abstract The palladium–salen complex palladium(II) N,N′-bis{[5-(triphenylphosphonium)-methyl]salicylidene}-1,2-ethanediamine chloride was found to be a highly active catalyst for the copper- and solvent-free coupling reaction of terminal alkynes with different acyl chlorides in the presence of triethylamine as base, giving excellent ynones under aerobic conditions.