Lanthanide-catalyzed deamidative cyclization of secondary amides and ynones through tandem C–H and C–N activation†
Abstract
The tandem inert α-C–H and C–N bond activation of amides represents a highly valuable but challenging transformation in organic synthesis. Herein, a simple rare earth metal amido complex has been shown to catalyse unprecedented cyclization of amides with ynones to form trisubstituted 2-pyrones. This protocol significantly enables the selective merger of inert α-C–H and C–N bond activations of amides and indicates a particular role of rare earth catalysts in enhancing the selectivity for the α-C–H bond of amides in the presence of N–H bonds.