Cobalt-Catalyzed Methylselenation of Boronic Reagents with PhSO2SeCH3

A bench-stable, easy-to-handle, and feasible scalable methylselenating reagent PhSO2SeCH3 was designed and prepared. An array of aryl boronic reagents could undergo electrophilic methylselenation with PhSO2SeCH3 in the presence of CoCl2 and 1,10-Phen to access functionalized arylmethyl selenides, which have important applications in the discovery of antineoplastic drugs. The powerful synthetic applications were demonstrated in late-stage methylselenation of bioactive molecules, 2-fold methylselenation of aryl boronic acids, trideuteromethylselenation and derivative modification of the product.