N- vs. O-Acylation of 1,2-Diazetidin-3-one: 4,5-Dihydro-1,3-oxadiazin-6-ones by Ring Enlargement

Article abstract of DOI:10.1021/jo00186a026

Treatment of 1,2-diazetidin-3-one with acid chlorides in the presence of 2,6-lutidine led to 1,2-diacyl-1,2-diazetidin-3-ones (N,N-diacylation), while the use of triethylamine as base gave 1-acyl-3-(acyloxy)-1,4-dihydro-1,2-diazetes (N,O-diacylation).Several 1-benzhydryl-2-acyl-1,2-diazetidin-3-ones were found to rearrange smoothly upon treatment with ethyl chloroformate to give 2-substituted 4-benzhydryl-4,5-dihydro-1,3,4-oxadiazin-6-ones.