Enantio- and Diastereoselective Copper-Catalyzed Borylative Coupling of Styrenes and Azadienes.

Here we disclose a CuB-catalyzed reaction between aurone-derived α,ß-unsaturated imines and styrenes to produce 2-substituted benzofuran derivatives bearing both the γ-boryl functionality and α,ß-unsymmetric stereogenic centers. The reaction represents the first transition-metal-catalyzed unsymmetric 1,4-Michael additions of azadienes, which would enrich the arsenal of CuB catalysis in organic synthesis. In addition, the synthetically versatile boron-alkylated products can be elaborated by chemical transformations to useful optically active benzofuran heterocycles.

Enantio- and Diastereoselective Copper-Catalyzed Synthesis of Chiral Aziridines with Vicinal Tetrasubstituted Stereocenters.

A Cu-catalyzed coupling of cyclic imino esters with 2H-azirines has been developed to synthesize novel optically active aziridines in high yields with excellent levels of diastereo- and enantioselectivities under mild conditions. This novel protocol features a broad substrate scope and good functional group compatibility, and it enriches the existing reaction type of rapid synthesis of optically active aziridines bearing vicinal tetrasubstituted stereogenic carbon centers.