Palladium-catalyzed stereoselective ring-opening reaction of aryl cyclopropyl ketones.

Herein, we report that α,β-unsaturated ketones could be obtained by palladium-catalyzed ring-opening of mono-substituted cyclopropyl ketones efficiently and systematically. ( E )-1-Arylbut-2-en-1-ones were generated from aryl cyclopropyl ketones stereoselectively in yields of 23-89% by the Pd(OAc) 2 /PCy 3 catalytic system. The reaction exhibited stereoselectivity (only E products were found) and was suitable for both phenyl and heteroaryl cyclopropyl ketones.