Visible-Light-Mediated Ipso-Carboacylation of Alkynes: Synthesis of 3-Acylspiro[4,5]trienones from N-(p-Methoxyaryl)propiolamides and Acyl Chlorides.

A novel visible-light-mediated ipso-carboacylation of N-(p-methoxyaryl)propiolamides with acyl chloride has been established for the synthesis of diverse 3-acylspiro[4,5]trienones with high selectivity and efficiency. This method represents a new difunctionalization of alkynes through cross coupling of the acyl chloride C-Cl bonds with an ipso-aromatic carbon by simultaneously forming two new carbon-carbon bonds and one carbon-oxygen double bond.