ACYLATION OF ALDO 1-PYRROLINE 1-OXIDES (4,5-DIHYDRO-3H-PYRROLE 1-OXIDES) AND THE OXIDATION OF THE RESULTING 3-ACYLOXY-1-PYRROLINES (3-ACYLOXY-4,5-DIHYDRO-3H-PYRROLES)

5,5-Dimethyl-1-pyrroline 1-oxide (DMPO), when treated with NaH (1 mol) followed by ethyl chloroformate, benzoyl chloride, pivaloyl chloride or 2-bromoisobutyryl bromide gave the corresponding 3-acyloxy-1-pyrrol ines. With NaH (2-4 mel) followed by benzoyl chloride or 2-bromoisobut yryl bromide, DMPO gave the corresponding -acyloxy-1'-pyrrolin-3'-yl)- 3-acyloxypyrrolidines. Acylation of the 3-phenyl and 3-methyl DMPOs al so gave the corresponding 3-acyloxy-1-pyrrolines. Oxidation of the 3-a cyloxy-1-pyrrolines with m-CPBA gave the corresponding oxaziridines in good yield. These oxaziridines were resistant to ring opening by acid hydrolysis, photolysis and thermolysis.