Preparation and characterisation of new oxovanadium(IV) Schiff base complexes derived from salicylaldehyde and simple dipeptides

A range of mostly new oxovanadium(IV) complexes is described. They contain coordinated Schiff bases, made from simple dipeptides (glycylglycine, glycylsarcosine, l-alanylglycine, l-alanyl-l-alanine, d,l-alanyl-d,l-alanine and l-serylglycine), and salicylaldehyde. The compounds are characterised and the nature of their coordination spheres shown by analysis, TLC, by appropriate spectroscopy (EPR, IR, electronic and circular dichroism of solution and solids) and by magnetic susceptibility measurements. Serylglycine and threonylglycine are formed by reaction of VO(salGlyGly) with formaldehyde and acetaldehyde, respectively.