A new route to the synthesis of (E)- and (Z)-2-alkene-4-ynoates and nitriles from vic-iiodo-(E)-alkenes catalyzed by Pd(0) nanoparticles in water.

An efficient procedure for the stereoselective synthesis of (E)- and (Z)-2-alkene-4-ynoates and -nitriles by a simple reaction of vic-diiodo-(E)-alkenes with acrylic esters and nitriles catalyzed by in situ prepared Pd(0) nanoparticles in water has been developed. Addition of acrylic esters leads to (E)-isomers exclusively, whereas (Z)-isomers are obtained in high stereoselectivity from reactions of acrylonitrile. The aqueous slurry of Pd nanoparticles is recycled. A probable mechanism has been suggested.