Palladium(II)-promoted cross-coupling of 4-alkenyl-2-azetidinones with organomercurials
摘要:
The palladium-promoted cross-coupling of 4-alkenyl-2-azetidinones with aryl and vinylic mercurials provides 5-aryl-3-alkenamides and 3,6-alkadienamides, respectively. Modest to excellent stereoselectivity for formation of the new carbon-carbon double bond is observed. The reaction becomes catalytic in palladium when cupric chloride and oxygen are introduced. This process constitutes the first organometallic ring opening of 2-azetidinones to acyclic unsaturated amides.