Iron-Catalyzed Cross-Dehydrogenative Coupling Esterification of Unactive C(sp³)–H Bonds with Carboxylic Acids for the Synthesis of α‑Acyloxy Ethers

Abstract

An iron-catalyzed oxidative esterification reaction between unactivated C­(sp³)–H bonds from symmetric and asymmetric ethers and carboxylic acids using di-<i>tert</i>-butyl peroxide (DTBP) as the oxidant via a cross dehydrogenative coupling (CDC) reaction was established, which tolerates a wide range of cyclic ether substrates to react with aromatic acids and phenylacetic acid, providing an efficient method for the preparation of α-acyloxy ethers with good to excellent yields. Intermolecular competing kinetic isotope effect (KIE) experiments were also carried out, which indicate that C­(sp³)–H bond cleavage may be the rate-determining step of this CDC reaction