Palladium mediated synthesis of conjugate (E) or (Z) enones and unsymmetrical divinyl ketones. One-pot preparation of Isoegomaketone

The palladium (o) catalyzed coupling of acyl halides or anhydrides with alkenyl copper reagents furnishes a,ß ethylenic ketones and a,ß-a,ß' diethylenic ketones in high yield. The substitution pattern of the alkenyl copper reagent, directly obtained by carbocupration of alkynes, is fully retained. Anhydrides of Z-ethylenic acids also retain their Z stereochemistry. ß-halogeno-vinyl ketones react under the above conditions to afford a,ß-?,d dienones. An efficient one-pot synthesis of Z or var epsilon isoegomaketone is reported