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
作者:Richard M. Hartshorn、Shane G. Telfer
DOI:10.1039/a904486h
日期:——
The products from the steady state photolysis of [Co(aa)(2,2â²-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(2,2â²-bpy)]+ complex ions. This contrasts with photolyses in aqueous solution where the [Co(2,2â²-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(2,2â²-bpy)y](3âx)+ compounds and are used to help rationalise the observed selectivity. Two of the products have been characterised by X-ray crystallography: (Î-SS/Î-RR)-trans(N)-[Co(ala)2(2,2â²-bpy)]ClO4·H2O and trans(N)-[Co(aib)2(2,2â²-bpy)]ClO4· NaClO4·0.5H2O.
在二甲基亚硫酰胺(dmso)中,[Co(aa)(2,2′-bpy)2]2+(aa = 甘氨酸(gly)、丙氨酸(ala)或2-氨基异丁酸(aib))络合物的稳态光解生成的产物已被鉴定,包括trans(N)-[Co(aa)2(2,2′-bpy)]+络合物离子。这与水溶液中的光解反应形成[Co(2,2′-bpy)3]3+离子形成对比。这种溶剂依赖性可归因于光解产物的二次反应,而不是不同的光化学反应。针对一系列[Co(aa)x(2,2′-bpy)y](3–x)+化合物收集了电化学数据,以帮助解释观察到的选择性。两个产物通过X射线晶体学进行了表征:(Δ-SS/Λ-RR)-trans(N)-[Co(ala)2(2,2′-bpy)]ClO4·H2O和trans(N)-[Co(aib)2(2,2′-bpy)]ClO4·NaClO4·0.5H2O。