Vicinal Diboronates in High Enantiomeric Purity through Tandem Site-Selective NHC-Cu-Catalyzed Boron-Copper Additions to Terminal Alkynes

摘要

We recently reported a site- and enantioselective Cu-catalyzed method for boron-copper addition to olefins carried out with bis(pina-colato)diboron [B_2(pin)_2; 1]. The transformations involve N-hetero-cyclic carbene (NHC) complexes and are performed in the presence of MeOH, which promotes in situ protonation of the C-Cu bond to regenerate the catalyst and deliver the hydroboration product.