Copper-Catalyzed N-Alkenylation of Azidoformates With Alkenyl Boronic Acids: Synthesis of N-Alkenylcarbamates

We report a copper-catalyzed N-alkenylation of azidoformates with a range of alkenyl boronic acids, providing an efficient and practical method for the synthesis of N-alkenylcarbamates. The reaction proceeds at room temperature in an open flask using CuCl as the sole catalyst, without the need for added base or ligand. A broad spectrum of alkenyl boronic acids, including styryl, α-substituted, cyclic, and heteroaryl derivatives, couples smoothly with diverse azidoformates to afford the corresponding enecarbamates in good to excellent yields. The method is operationally simple and readily scalable. Representative downstream transformations further demonstrate the synthetic utility of the products. Control experiments are consistent with the involvement of a nitrene-type intermediate in the reaction pathway.