Palladium(II) catalyzed carbonylative dimerization of allenyl ketones: efficient synthesis of difuranylketones

Abstract Palladium(II) catalyzed carbonylation of 1,2-allenyl ketones 1 in the presence of p -benzoquinone (1 equiv) under a CO atmosphere (balloon) afforded difuranylketones 4 in moderate to good yields. Mechanistically, the electron-withdrawing nature of the acyl group should enhance the electrophilicity of the acylpalladium species B , and thus promote the oxypalladation of an additional molecule of 1 , leading to the difuranyl ketone 4 .