Catalytic asymmetric ring-opening of aminocyclopropanes with oxygen nucleophiles: access to chiral γ-amino acid derivatives

Donor-acceptor aminocyclopropanes containing both amino and carboxyl groups underwent efficient catalytic asymmetric ring-opening reactions with diverse oxygen nucleophiles to afford chiral gamma-oxygen-substituted gamma-aminobutyric acid derivatives in 60-96% yields and 70-99% ee. With imidazoline-pyrroloimidazolone pyridine as the chiral ligand, a broad range of oxygen nucleophiles, including alcohols, phenols, carboxylic acids, 4-hydroxycoumarins and 1,3-cyclodiones are compatible. The developed method was applied to the derivatization of complex molecules including (-)-myrtenol, stavudine, (S)-naproxen, and (-)-estrone. Donor-acceptor aminocyclopropanes bearing both amino and carboxyl groups underwent catalytic asymmetric ring-opening reactions with diverse oxygen nucleophiles to afford chiral gamma-oxygen-substituted gamma-aminobutyric acid derivatives with good results.