Hydrogen Atom and Hydride Transfer in the Reactions of Chromium(IV) and Chromium(V) Complexes with Rhodium Hydrides. Crystal Structure of a Superoxorhodium(III) Product
作者:Andreja Bakac、Ilia A. Guzei
DOI:10.1021/ic991098p
日期:2000.2.1
s(-1); (NH3)4, 2,500; L2, 1,000) and isotope effects (L = L1, kie = 5.4; L2, 6.2). The superoxo complex [L1(CH3CN)RhOO](CF3SO3)2.H2O crystallizes with discrete anions, cations, and solvate water molecules in the lattice. All moieties are linked by a network of hydrogen bonds of nine different types. The complex crystallized in the triclinic space group P1 with a = 9.4257(5) A, b = 13.4119(7) A, c = 13
在分子氧存在下,水溶液中的铬酸根离子Cr(IV)aqO2 +与氢化物L(H2O)RhH2 +(L = L1 = [14] aneN4和L2 = meso-Me6- [14] aneN4)反应,生成生成Cr(aq)3+和超氧配合物L(H2O)RhOO2 +。在25摄氏度时,速率常数约为10(4)M(-1)s(-1)(L = L1)和1.12 x 10(3)M(-1)s(-1)(L = L2 )。两种反应均显示出适度的氘同位素效应,kRhH / kRhD =约3(L1)和3.3(L2),但无溶剂同位素效应,kH2O / kD2O =1。提出的机理涉及氢原子的提取,然后捕获LRh( H2O)2+与分子氧。没有证据表明在L(H2O)RhH2 +和(salen)CrVO +之间的反应中会形成L(H2O)Rh2 +。建议的氢化物转移由速率常数的大小(L = L1,k = 8,800 M(-1)s(-1);(NH3)4,2,500;