Exploration of a Chiral Cobalt Catalyst for Visible-Light-Induced Enantioselective Radical Conjugate Addition

摘要

Chiral catalysts tolerating photochemical reactions are in great demand for the vast development of visible-light-induced asymmetric synthesis. Now, chiral octahedral complexes based on earth-abundant metal and chiral N-4 ligands are reported. One well-defined chiral Co-II-complex is shown to be an efficient catalyst in the visible-light-induced conjugated addition of enones by alkyl and acyl radicals, providing synthetically valued chiral ketones and 1,4-dicarbonyls in 47->99 % yields with up to 97:3 e.r.