A convenient asymmetric synthesis of (+)-cis-[VO(AA)(2) Cl]ClO4 (AA=bpy or phen) through air oxidation of binuclear [V-2 (AA)(4) (mu-Cl)(+)-tart)](3+) is reported. The CD spectra of (+)-cis-VO(AA)(2) Cl](+) and binuclear intermediates (+)-[V-2(AA)(4) (mu-Cl) (mu-(+)-tart)](3+) in aqueous solution were reported and assigned to electronic transitions.