Abstract

A highly-efficient method for the copper- and solvent-free coupling reaction of acid chlorides and terminal alkynes catalyzed by diatomite-supported palladium(II) salophen complex is described. Acid chlorides are easily coupled with terminal alkynes, giving good to high yields in the presence of a low catalyst loading (1 mol% Pd) in DIEA at room temperature under aerobic conditions. After centrifugation, the supported catalyst is able to be recycled and reused for several times with only a slight decrease in activity.

Keywords: Copper-free, sonogashira reaction, supported catalyst, acid chlorides, alkynyl, acylation, polystyrene-supported, bidentate, phosphine, palladium