Thermal Isomerization of 7,8-Diazabicyclo[4.2.2]deca-2,4,7,9-tetraene N-oxide to Benzaldehyde Oxime

Thermal transformation of 7,8-diazabicyclo[4.2.2]deca-2,4,7,9-tetraene N-oxide ( 3 ) was observed, (Z)-benzaldehyde oxime being the major product, with (E)-benzaldehyde oxime as a minor product. N-Oxide 3 was labeled with deuterium α to the oxidized N-atom. The location of the deuterium label in the thermolysis products fitted one of two reasonable mechanisms.