OXOVANADIUM(IV) COMPLEXES WITH 14-MEMBERED MACROCYCLIC LIGANDS DERIVED FROM DITHIOOXAMIDE

Oxovanadium(IV) complexes, [VO(L)]SO4, where L = 5, 7, 12, 14-R-4-2, 3 , 9, 10-S-4-[14]-1, 5, 7, 12-tetraene-1, 4, 8, 11-N-4 have been prepar ed in methanol. Tentative structures of the complexes have been propos ed on the basis of elemental analyses, electrical conductance, magneti c moment and spectral (IR, electronic and EPR) data. The X-band EPR sp ectra of all the complexes were recorded at room temperature and at li quid nitrogen temperature. The room temperature EPR spectra do not sho w anisotropy because of rapid tumbling of the molecules in solution bu t it is observed at liquid nitrogen temperature. The spectral studies support square pyramidal geometry for the oxovanadium (IV) complexes.