Thermal Dehydrogenation of Oxovanadium(IV) Complexes with Schiff Base Ligands Derived from meso-1,2-Diphenyl-1,2-ethanediamine in the Solid State

Schiff base−oxovanadium(IV) complexes, [VO(Xsal-meso-stien)] (X = 3-EtO, 5-MeO, 5-Br) were dehydrogenated upon heating at 210 °C for 3−15 h in the solid state in the air to form [VO(Xsalton)], which have a CC double bond in the five-membered chelate ring moiety. The structures of [VO(3-EtOsal-meso-stien)] and [VO(3-EtOsalton)] were determined by X-ray structure analyses. The benzylic carbon atoms of the N−N chelate ring of [VO(Xsal-meso-stien)] will be oxidized by oxygen in the air to form a double bond.