Enantioselective Ni-Catalyzed Electrochemical Synthesis of Biaryl Atropisomers

A scalable
enantio­selective nickel-catalyzed electro­chemical
reductive homocoupling of aryl bromides has been developed, affording
enantio­enriched axially chiral biaryls in good yield under mild
conditions using electricity as a reductant in an undivided cell.
Common metal reductants such as Mn or Zn powder resulted in significantly
lower yields in the absence of electric current under otherwise identical
conditions, underscoring the enhanced reactivity provided by the combination
of transition metal catalysis and electro­chemistry.

本研究开发了一种可规模化的对映选择性镍催化电化学还原均偶联反应，以芳基溴化物为底物，在无分隔电解池中以电能作为还原剂，于温和条件下以良好收率得到对映体富集的轴手性联芳类化合物。在其他条件完全一致且无电流通入的情况下，使用锰粉或锌粉等常见金属还原剂时，反应收率显著降低，这凸显了过渡金属催化与电化学联用所带来的反应活性提升。