PALLADIUM-CATALYZED COUPLING REACTIONS OF (ALPHA-ETHOXYVINYL)TRIMETHYLSTANNANE WITH VINYL AND ARYL TRIFLATES

The palladium-catalyzed cross-coupling reaction of vinyl triflates and halides with (α-ethoxyvinyl)trimethylstannane gives high yields of 2-ethoxy 1,3-dienes, which can be hydrolyzed to the corresponding α,β-unsaturated ketones. Aryl triflates undergo an analogous coupling reaction, providing a facile method for replacing the hydroxyl group of a phenol by an acyl group. The use of (α-ethoxyvinyl)trimethylstannane in palladium-catalyzed carbonylative coupling gives rise to vinyl and aryl α-ethoxyvinyl ketones and indirectly to the corresponding a-diketones (which result from their hydrolysis) and glyoxylates (which result from their ozonolysis). © 1990, American Chemical Society. All rights reserved.