Oxidative rearrangement of alkynes to chiral α-arylalkanoic esters

Abstract

Chiral α-arylalkanoic esters, valued as anti-inflammatory agents, are synthesised through an enantioselective oxidative rearrangement of alkynes under green, metal-free conditions. This study achieves this transformation using chiral iodine(III) reagents with para-toluenesulfonic acid and various alcohols, producing the esters in up to 91% yield and 99% enantiomeric excess. The scope of the reaction particularly includes electron-rich non-terminal arylalkynes. Density functional theory calculations give insight into the origin of enantioselectivities of this process.