Regioselective catalytic asymmetric N-alkylation of isoxazol-5-ones with para-quinone methides.
Suo-Suo QiZhen-Hui JiangMing-Ming ChuYi-Feng WangXue-Yang ChenWan-Zhen JuDan-Qian XuPublished in: Organic & biomolecular chemistry (2020)
A highly regioselective and enantioselective N-alkylation of isoxazol-5-ones with para-quinone methides promoted by bi-functional squaramide catalysts was developed. This unexpected asymmetric N-addition of isoxazolinones afforded a series of enantioenriched N-diarylmethane substituted isoxazolinones with high yields and enantioselectivities (up to 97 : 3 er). This reaction not only provides a useful approach for intermolecular chiral C-N bond formation but also demonstrates the immense potential of isoxazol-5-ones as N-nucleophiles in catalytic asymmetric reactions.