Reactions of group IV organometallic compounds. Part XXII. An extensive study on preparation of some oxadiazinones by the reaction of N-trimethylmetal(IV)dialkylamines with benzoyl isocyanate

Abstract

It is shown that benzoyl isocyanate (I) can be inserted into the metal–nitrogen bond of N-trimethylmetal(IV)dialkylamines (Me₃M·NR¹R²; M = Si, Ge, and Sn); the structures of the adducts are discussed. When (I) was treated with Me₃Si·NR¹R² in a 2 : 1 molar ratio trimethylsilyl benzoate was eliminated and 2-dialkylamino-6-phenyl-1,3,5-oxadiazin-4-one (VII) and/or 4,6-diphenyl-1,3,5-oxadiazin-2-one (XI) were isolated. The yields of (VII) and (XI) were influenced by alkyl substituents (R¹,R²). However, Me₃Sn·NMe₂ reacted with an excess of (I) to give 2,6-diphenyl-1,3,5-oxadiazin-4-one (XV) with evolution of carbon dioxide. The corresponding germanium compound showed behaviour intermediate between that of the analogous silicon and tin compounds.