Formation of trans(N)-bis(amino acidato)(2,2′-bipyridine)cobalt(III) complexes following the UV irradiation of amino acidatobis(2,2′-bipyridine)cobalt(III) complexes in dimethyl sulfoxide

The products from the steady state photolysis of [Co(aa)(2,2'-bpy)(2)](2+) (aa = glycinate (gly), alaninate (ala) or 2-aminoisobutyrate (aib)) complexes in dmso have been identified, and include the trans(N)-[Co(aa)(2)(2,2'-bpy)](+) complex ions. This contrasts with photolyses in aqueous solution where the [Co(2,2'-bpy)(3)](3+) ion is produced. This solvent dependence can be attributed to the secondary reactions of the photolysis products, rather than to different photochemistry. Electrochemical data have been gathered on a range of [Co(aa)(x)(2,2'-bpy)(y)]((3-x)+) compounds and are used to help rationalise the observed selectivity. Two of the products have been characterised by X-ray crystallography: (Delta-SS/Lambda-RR)-trans(N)-[Co(ala)(2)(2,2'-bpy)]ClO4. H2O and trans(N)-[Co(aib)(2)(2,2'-bpy)]ClO4. NaClO4. 0.5H(2)O.