N-Heterocyclic Carbene-Mediated Oxidative Electrosynthesis of Esters in a Microflow Cell

An efficient N-heterocyclic carbene (NHC)-mediated oxidative esterification of aldehydes has been achieved in an undivided microfluidic electrolysis C-ell at ambient temperature. Productivities of up to 4.3 g h(-1) in a single pass are demonstrated, with excellent yields, and conversions for 19 examples presented: Notably, the oxidative acylation, reactions were,shown to proceed with a 1:1 stoichiometry of aldehyde and alcohol (for primary alcohols), with remarkably short residence tithes in the electrolysis cell (<13 s), and without added electrolyte.