An improved procedure to prepare 3-methyl-4-nitroalkylenethylisoxazoles and their reaction under catalytic enantioselective Michael addition

Herein, we describe a short synthesis of 3-methyl-4-nitro-5-alkylethenyl isoxazoles and their reactivity as Michael acceptors. The title compounds reacted with nitromethane under phase-transfer catalysis to provide highly enantioenriched adducts (up to 93% ee) which were then converted to the corresponding gamma-nitroacids.