Understanding the Origin of One- or Two-Step Valence Tautomeric Transitions in Bis(dioxolene)-Bridged Dinuclear Cobalt Complexes
作者:Gemma K. Gransbury、Brooke N. Livesay、Jett T. Janetzki、Moya A. Hay、Robert W. Gable、Matthew P. Shores、Alyona Starikova、Colette Boskovic
DOI:10.1021/jacs.0c01073
日期:2020.6.17
Bis(dioxolene)-bridged dinuclear cobalt compounds provide an avenue toward controlled two-step valence tautomeric (VT) interconversions of the form CoIII-cat-cat-CoIII} ⇌ CoIII-cat-SQ-CoII} ⇌ CoII-SQ-SQ-CoII} (cat2- = catecholate, SQ•- = semiquinonate). The four dinuclear cobalt complexes in this study are bridged by deprotonated 3,3,3',3'-tetramethyl-1,1'-spirobi(indan)-5,5',6,6'-tetraol (spiroH4)
双(二氧戊环)-桥连双核钴化合物为 CoIII-cat-cat-CoIII} ⇌ CoIII-cat-SQ-CoII} ⇌ CoII-SQ 形式的受控两步价互变异构 (VT) 互变提供了途径-SQ-CoII}(cat2- = 儿茶酚酸盐,SQ•- = 半醌酸盐)。本研究中的四种双核钴配合物由去质子化的 3,3,3',3'-四甲基-1,1'-螺二(茚满)-5,5',6,6'-四醇(spiroH4)或 3 ,3,3',3'-tetramethyl-1,1'-spirobi(indan)-4,4',7,7'-tetrabromo-5,5',6,6'-tetraol (Br4spiroH4) 与 Mentpa 辅助配体(tpa = 三(2-吡啶基甲基)胺,n = 0-3 对应于吡啶环 6 位的甲基化)。互补的结构、磁性、光谱和 DFT 计算研究揭示了四种钴配合物的不同电子结构和 VT 行为;