Asymmetric synthesis of 4-amino-3,4-dihydro-2,2-dimethyl-2H-1 benzopyrans

Article abstract of DOI:10.1016/S0040-4020(99)00376-2

Highly enantioselactive reduction of 3,4-dihydro-2,2-dimethyl-2H-1- benzopyran-4-ones 3 a-e by BH₃ was achieved in the presence of catalytic amounts of Corey's oxazaborolidine 4 to afford the corresponding 3,4-dihydro- 2,2-dimethyl-2H-1-benzopy