Electrochemical cobalt-catalyzed semi-deuteration of alkynes to access deuterated Z-alkenes

Abstract Deuterium labeling has found extensive applications across various research fields, including organic synthesis, drug design, and molecular imaging. Electrocatalytic semi-hydrogenation of alkynes offers a viable route for the synthesis of Z -alkenes, yet it falls short in achieving the semi-deuteration of these compounds. In this study, we report an electrochemical cobalt-catalyzed transfer deuteration reaction that proficiently accomplishes the semi-deuteration of alkynes, yielding Z -configuration deuterated alkene products. This reaction utilizes cost-effective cobalt salts as catalysts and employs D 2 O and AcOD (acetic acid- d ) as economical and efficient deuterium sources, underscoring its practicality and feasibility. The reaction demonstrates a broad alkyne substrate scope, high reaction efficiency, good functional group compatibility, excellent Z -selectivity, and a remarkable degree of deuteration rate.