1,3‐Iodoesterification of 2‐Substituted Indoles via Csp2−H/Csp3−H Retained Dual Functionalization Using Hypervalent Iodine(III)

Abstract

AbstractA 1,3‐iodoesterification of 2‐substituted indoles with trihaloacetic acid, iodination reagent, and hypervalent iodine(III) compound was developed as an acid‐promoted Csp2−H/Csp3−H dual functionalization reaction to furnish 3‐iodo‐2‐trihaloacetoxymethyl indoles. The one‐pot 1,3‐iodoesterification/hydrolysis of the trihaloester group provided 3‐iodo‐2‐pivaloylmethyl indoles via the rearrangement of the pivaloyl group. The reaction proceeded through a trihaloacetic acid‐assisted electrophilic activation of the iodination reagent after the formation of an indolyl(mesityl)iodonium trihaloacetate.