Synthesis and Reactions of a Hypervalent Iodine-Benzyne Precursor Possessing an Ester Group

Abstract

The Diels-Alder reaction of methyl 2-pyrone-5-carboxylate and bis(trimethylsilyl)acetylene gave methyl 3,4-bis(trimethylsilyl)-benzoate which was transformed into [5-(methoxycarbonyl)-2-(trimethylsilyl)phenyl](phenyl)iodonium triflate by the reaction with a hypervalent iodine reagent PhI(OAc)2/TfOH. The generation and trapping reactions of 4-(methoxycarbonyl)-1,2-didehydrobenzene were successfully conducted by the reaction of the iodonium triflate with Bu4NF.