Regio and diastereoselective addition of imidazoline 3-oxides to aryl isocyanates
摘要:
Delta(3)-Imidazoline 3-oxides 1 underwent regio and diastereoselective cycloaddition with aryl isocyanates 2 to give 5,6,7,7a-tetrahydroimidazo[1,5-(b) under bar][1,2,4]oxadiazol-2(1 (H) under bar)-ones 3 in excellent yields. Thermally and chemically induced retro cycloaddition of compounds 3 was demonstrated. (C) 1997 Elsevier Science Ltd.
Beckmann Fragmentation of Diphenylcarbamoylated N-Aryldiphenacylamine Dioximes. New Method for the Synthesis of Imidazooxadiazolones
摘要:
N-Aryl-N,N-diphenacylamine dioximes were prepared by the reaction of corresponding arylamines with alpha-bromoacetophenone oxime in ethanol-water at room temperature. These compounds reacted with aryl isocyanates in acetonitrile to give imidazooxadiazolones 9. The probable mechanism of the reaction is discussed.