Synthesis of α-pyrones via gold-catalyzed cycloisomerization/[2+1] cycloaddition/rearrangement of enyne-amides and sulfur ylides

A novel gold-catalyzed cycloisomerization/[2 + 1]cycloaddition/[1,3]-sigmatropic rearrangement sequence of readily available acyclic enyne-amides and sulfur ylides is reported. This strategy enables rapid and efficient construction of a series of alpha-pyrone derivatives with diverse substituents. Based on several control experiments, a possible mechanism was also proposed to rationalize the cascade process.

Automated summary

A novel gold-catalyzed cascade reaction involving cycloisomerization, [2+1] cycloaddition, and [1,3]-sigmatropic rearrangement has been developed for the synthesis of alpha-pyrone derivatives. This strategy allows for the rapid and efficient construction of diverse alpha-pyrone derivatives using readily available starting materials. The proposed mechanism was supported by control experiments.