Copper‐Catalyzed Dehydrogenative Coupling of Arenes with Alcohols

Abstract

Scheme 1. Dehydrogenative alkoxylation of arenes. DG = directing group, FG = functional group, Alk = alkyl.[*] Dr. Scheme 2. Dehydrogenative alkoxylation of an C sp 3ÀH bond.Scheme 3. Determination of the kinetic isotope effect.Scheme 4. Evidence against the formation of hydroxyarene intermediates.Scheme 5. Proposed dehydrogenative alkoxylation mechanism. Angewandte Chemie

Copper-Mediated Intermolecular C–H/C–H and C–H/N–H Couplings via Aromatic C–H Cleavage

“…38) [69]. Unfortunately, phenols in place of the alcohols result in no formation of the C-O coupling products, due to the dominant self-coupling under oxidative conditions.…”

Recent advances in copper-mediated chelation-assisted functionalization of unactivated C–H bonds

“…16b,16e,16f The bimetallic copper/silver system was further extended to the regiospecific dehydrogenative cross-coupling of arenes and alcohols with the assistance of pyridine, pyrimidine or pyrazole (Scheme 40b). 46 These reactions were proposed to go through Ar-Cu(III)-OR intermediates 100 and 103. Although copper(II)-mediated C−H oxidation has been well investigated, the mechanisms of many of these reactions remain unclear.…”

Development of new methods in modern selective organic synthesis: preparation of functionalized molecules with atomic precision

“…157 Presumably, the copper ion is inserted into the C7H bond of the aromatic ring, the Cu II complex thus formed is oxidized by silver(I) ions to a Cu III complex and the C7O bond is formed upon reductive elimination. The drawbacks of the method are the use of large amounts of silver triflate and alcohol (serving as the solvent) and high temperature of the synthesis.…”