Mechanistic studies of O2 reduction effected by group 9 bimetallic hydride complexes.
Mechanistic studies of O2 reduction effected by group 9 bimetallic hydride complexes.
复制标题
第 9 族双金属氢化物配合物影响 O2 还原的机理研究。
DOI：
--
复制
发表时间：
2011
影响因子：
15
通讯作者：
D. Nocera
中科院分区：
文献类型：
--
作者：
Thomas S. Teets;D. Nocera
合成和动力学研究被用来揭示氧化还原成水的机制细节介导的镉配合物。混合价Rh(2)(0，II)(tfepma)(2)(CN(t)Bu)(2)Cl(2) (1), tfepma = MeN[P(OCH(2)CF(3))（2)]（2)， CN(t)Bu =叔丁基异氰酸酯））配合物被HCl质子化生成Rh(2)(II，II)(tfepma)(2)(CN(t)Bu)(2)Cl(3)H(2)，促进O(2)还原为水，同时生成Rh(2)(II，II)(tfepma)(2)(CN(t)Bu)(2)Cl(4)(3)。类似的二铱配合物的反应允许鉴定合理的反应中间体。Ir(2)(0,ii)(tfepma)(2)(CN(t)Bu)(2)Cl(2)(4)可以质子化形成可分离的络合物Ir(2)(II，II)(tfepma)(2)(CN(t)Bu)(2)Cl(3)H(5)，与O(2)反应形成Ir(2)(II，II)(tfepma)(2)(CN(t)Bu)(2)Cl(3)(OOH)(6)。此外，4与O(2)反应生成Ir(2)(II，II)(tfepma)(2)(CN(t)Bu)(2)Cl(2)(η(2)-O(2))(7)，可被HCl质子化生成6。配合物6和7均以纯形式分离得到，并进行了结构和光谱表征。氢化物配合物5与O(2)和HCl的动力学研究提供了与HCl消除机制一致的速率定律，其中O(2)结合Ir(0)中心生成中间η(2)-过氧化物中间体。同系物Dirhodium 2遵循的速率定律不仅与类似的hcl消除机制一致，而且还包括指示直接O(2)插入和在氧化之前的单分子异构化的术语。综合合成和机理研究表明过氧化物和氢过氧化物中间体在氢化二钠配合物将O(2)还原为水中的重要性。
Synthetic and kinetic studies are used to uncover mechanistic details of the reduction of O(2) to water mediated by dirhodium complexes. The mixed-valence Rh(2)(0,II)(tfepma)(2)(CN(t)Bu)(2)Cl(2) (1, tfepma = MeN[P(OCH(2)CF(3))(2)](2), CN(t)Bu = tert-butyl isocyanide) complex is protonated by HCl to produce Rh(2)(II,II)(tfepma)(2)(CN(t)Bu)(2)Cl(3)H (2), which promotes the reduction of O(2) to water with concomitant formation of Rh(2)(II,II)(tfepma)(2)(CN(t)Bu)(2)Cl(4) (3). Reactions of the analogous diiridium complexes permit the identification of plausible reaction intermediates. Ir(2)(0,II)(tfepma)(2)(CN(t)Bu)(2)Cl(2) (4) can be protonated to form the isolable complex Ir(2)(II,II)(tfepma)(2)(CN(t)Bu)(2)Cl(3)H (5), which reacts with O(2) to form Ir(2)(II,II)(tfepma)(2)(CN(t)Bu)(2)Cl(3)(OOH) (6). In addition, 4 reacts with O(2) to form Ir(2)(II,II)(tfepma)(2)(CN(t)Bu)(2)Cl(2)(η(2)-O(2)) (7), which can be protonated by HCl to furnish 6. Complexes 6 and 7 were both isolated in pure form and structurally and spectroscopically characterized. Kinetics examination of hydride complex 5 with O(2) and HCl furnishes a rate law that is consistent with an HCl-elimination mechanism, where O(2) binds an Ir(0) center to furnish an intermediate η(2)-peroxide intermediate. Dirhodium congener 2 obeys a rate law that not only is also consistent with an analogous HCl-elimination mechanism but also includes terms indicative of direct O(2) insertion and a unimolecular isomerization prior to oxygenation. The combined synthetic and mechanistic studies bespeak to the importance of peroxide and hydroperoxide intermediates in the reduction of O(2) to water by dirhodium hydride complexes.
登录
查看更多内容
影响因子：
4.6
作者：
Nocera, Daniel G.
通讯作者：
Nocera, Daniel G.
影响因子：
15
作者：
Fukuzumi S;Kotani H;Lucas HR;Doi K;Suenobu T;Peterson RL;Karlin KD
通讯作者：
Karlin KD
影响因子：
15
作者：
Dogutan, Dilek K.;Stoian, Sebastian A.;Nocera, Daniel G.
通讯作者：
Nocera, Daniel G.
影响因子：
15
作者：
Chang, CJ;Loh, ZH;Nocera, DG
通讯作者：
Nocera, DG