Synthesis of 3-benzenesulfonylisoxazolines and isoxazolidines

Isoxazoline derivs., e.g. I, were obtained in moderate yields upon refluxing a HCCl3 soln. of electron-rich or moderate electron-poor dipolarophiles and PhSO2CH:N(O)OMe. Electron-poor dipolarophiles react with PhSO2CH:N(O)OMe yielding N-methoxyisoxazlidines, e.g., II.