Visible-light-induced tandem difluoroalkylated spirocyclization of N-arylpropiolamides: access to C3-difluoroacetylated spiro[4,5]trienones

A visible-light-catalyzed difluoroacetylated spirocyclization of N-arylpropiolamides with ethyl bromodifluoroacetate as a CF2CO2Et radical precursor is described. This approach allows the formation of two carbon-carbon bonds and one carbon-oxygen bond in a single reaction through a sequence of C-H oxidative coupling, ipso-cyclization and dearomatization processes. This protocol affords a straightforward route to synthesize CF2CO2Et-containing spiro[4.5]trienones in moderate to good yields.

Automated summary

A visible-light-catalyzed difluoroacetylated spirocyclization reaction of N-arylpropiolamides with ethyl bromodifluoroacetate as a CF2CO2Et radical precursor is described. This approach enables the formation of two carbon-carbon bonds and one carbon-oxygen bond in a single reaction through a sequence of C-H oxidative coupling, ipso-cyclization, and dearomatization processes, providing a straightforward route to synthesize CF2CO2Et-containing spiro[4.5]trienones in moderate to good yields.