A facile method for the preparation of 4-hydroxy-Δ2-isoxazolines via a cycloaddition/oxidation procedure employing nitrile oxides and vinylboronic esters

Article abstract of DOI:10.1016/S0040-4039(00)78326-2

The 1,3-dipolar cycloaddition of aromatic nitrile oxides with trans-1,2-disubstituted vinylboronic esters affords the 4-boronic ester substituted Δ²-isoxazoline as the major regioisomer. If the reaction mixture is treated with t-BuOOH the corre