Synthesis of Masked α, β-Unsaturated Trifluoromethyl Ketones via Iodine(III)-Mediated Double Decarboxylative Trifluoroacetylation

Abstract

An iodine(III)-mediated double decarboxylative trifluoroacetylation of masked α, β-unsaturated carboxylic acids with cyclic CF₃-pyruvate acetals is reported. This metal-free protocol employs PhI(OCOMe)₂ as a dual-function decarboxylative reagent to forge the C–C bonds via a radical pathway, delivering a diverse array of masked α, β-unsaturated trifluoromethyl ketones under simple thermal conditions with broad functional group tolerance. Gram-scale synthesis and downstream transformations highlight the synthetic utility, while mechanistic studies implicate sequential single-electron transfer and decarboxylation events.