Imidazolidine-Pyrroloimidazolone Pyridine-Cu(OTf)₂ Complex Catalyzed Asymmetric Radical Carbo-Esterification

Highly enantioselective radical carbo-esterification of iodoacetic acid with alkenes was achieved under mild conditions with 5 mol % of a chiral copper complex as the catalyst. With Cu(OTf)₂ as Lewis acid and C₁-symmetric imidazolidine-pyrroloimidazolone pyridine as the ligand, various chiral γ-butyrolactones were obtained in good yields (up to 99% yield) and high enantioselectivities (up to 97% ee). Chiral γ-butyrolactones can be efficiently converted into key chiral building blocks with high enantioselectivity via ring-opening amination and are applicable to the synthesis of antidepressant drugs and other bioactive molecules.