Synthesis of delta,delta-Diaryl-alpha-cyanoacrylamides and delta,delta-Diarylallylidiene Malononitriles by Pd(OAc)(2) Catalyzed Mizoroki-Heck Reaction

摘要

An expeditious route for the stereoselective catalytic monohydration of nitrile and ' CN ' directed regio-stereoselctive delta-arylation of various arylallylidene malononitriles affording delta, delta-Diaryl-alpha-cyanoacrylamides in hydrolysis condition and delta, delta-Diarylallylidene malononitriles in anhydrous condition by Pd(OAc)(2) catalyzed Mizoriki-Heck reaction is described. This provides an instantaneous formation of a library of compounds in a very short time period and simple operational process. The structure elucidation of the diastereomers was done by HMBC, HSQC, 2-D NMR experiments and X-ray single crystallographic analysis. A probable reaction mechanism directed by nitriles and involvement of syn and anti pi-allylic Pd-complexes has been proposed that is in consonance with the experimental findings and product distributions.