Amide Oxime Functions as Neighbouring Groups in Cyclodehydrogenation Reactions
Dehydrogenation of the o‐(tertiary amino)benzamide oximes 4, which are monosubstituted at the amide N atom of the neighbouring group, by the mercury edta complex yields tricyclic amino nitrones 9 with a quinazoline 3‐oxide moiety or lactams 8. Product formation depends on the nature of the N substituent, the size of the amine ring, and the reaction conditions. The configuration of the amide oximes and the conformation of the tricyclic systems is determined by NMR‐spectroscopic methods.