Stereoselective syntheses of heterocycles via metallated alkoxyallenes

Abstract

n-Butyllithium smoothly deprotonates alkoxyallenes at C-1. The generated lithiated species reacts with a variety of electrophiles furnishing after cyclization functionalized furan, pyrrole, or 1,2-oxazine derivatives. The formation of new C-C bonds often occurs with high stereoselectivities, which are exploited for efficient and selective syntheses of natural products or other compounds of interest.