2,2′-Biaryldicarboxylate Synthesis via Electrocatalytic Dehydrogenative C–H/C–H Coupling of Benzoic Acids

2,2′-Biaryldicarboxylates are important functionalities in bioactive compounds, functional materials, and chiral catalysts. These compounds have been found to be conveniently accessible from benzoic acids via Rh-catalyzed electrooxidative C–H/C–H couplings, giving valuable dihydrogen as the byproduct. In an undivided cell with Pt electrodes, RhCl3·3H2O catalyzes the oxidative carboxylate-directed ortho-homocoupling of various aromatic acids with a current efficiency of 67%. The protocol is operationally simple, tolerates a wide variety of functional groups, and does not require the exclusion of air and moisture. Heterodimerizations via cross-dehydrogenative couplings of naphthyl-1-carboxylic acids with acrylic or benzoic acids were also shown to work.