摘要:
The alpha-chalcogene-substituted formylolefinations of ketones and aldehydes proceeded using 1-lithio-2-ethoxyvinyl chalcogenides/PPSE or TMSOTf produce the alpha-chalcogenoformylolefinated products 4a-1 in high yields. Tandem-formylolefination provided the (2Z,4Z)-2,4-bis(chalcogeno)pent-2,4-dienals 5d,h,i and (2Z,4Z,6Z)-2,4,6-tris(phenylthio)hept-2, derivatives 7d and 8d, respectively.