Solvent influence on the thermodynamics for hydride transfer from bis(diphosphine) complexes of nickel.
Solvent influence on the thermodynamics for hydride transfer from bis(diphosphine) complexes of nickel.
复制标题
溶剂对镍双（二膦）配合物氢化物转移热力学的影响。
作者：
Samantha J Connelly Robinson;Christopher M. Zall;Deanna L. Miller;J. Linehan;A. Appel
金属氢化物的热力学水合性在不同溶剂之间可以有很大的不同。该参数可用于确定氢化物转移反应的有利性，例如金属氢化物与CO2之间生成甲酸盐的反应。由于这些物质的水合度在溶剂之间不一致，因此在一种溶剂中化学上不利的反应在其他溶剂中可能是有利的。将水溶性双膦氢化镍络合物的水合性与甲酸盐在水和乙腈中的水合性进行比较。在乙腈中，甲酸盐是比[HNi（dmpe）2]（+）好7 kcal mol（-1）的氢化物给体，在该溶剂中没有发生[HNi（dmpe）2]（+）向CO2的氢化物转移。相对于乙腈，[HNi（dmpe）2]（+）在水中的水合性大大提高，因为发现[HNi（dmpe）2]（+）将CO2还原成甲酸盐的还原性下降了8 kcal mol（-1）。对CO_2的加氢进行了催化研究，但在催化条件下[HNi（dmpe）_2]的再生是不利的。然而，目前的结果表明，溶剂的热力学参数，如水合度和酸度的依赖性，可以利用，以产生平衡或有利的整体热力学系统。这种方法应该是有利的，为未来的水溶性催化剂的设计。
The thermodynamic hydricity of a metal hydride can vary considerably between solvents. This parameter can be used to determine the favourability of a hydride-transfer reaction, such as the reaction between a metal hydride and CO2 to produce formate. Because the hydricities of these species do not vary consistently between solvents, reactions that are thermodynamically unfavourable in one solvent can be favourable in others. The hydricity of a water-soluble, bis-phosphine nickel hydride complex was compared to the hydricity of formate in water and in acetonitrile. Formate is a better hydride donor than [HNi(dmpe)2](+) by 7 kcal mol(-1) in acetonitrile, and no hydride transfer from [HNi(dmpe)2](+) to CO2 occurs in this solvent. The hydricity of [HNi(dmpe)2](+) is greatly improved in water relative to acetonitrile, in that reduction of CO2 to formate by [HNi(dmpe)2](+) was found to be thermodynamically downhill by 8 kcal mol(-1). Catalysis for the hydrogenation of CO2 was pursued, but the regeneration of [HNi(dmpe)2] under catalytic conditions was unfavourable. However, the present results demonstrate that the solvent dependence of thermodynamic parameters such as hydricity and acidity can be exploited in order to produce systems with balanced or favourable overall thermodynamics. This approach should be advantageous for the design of future water-soluble catalysts.
三烷基硼烷辅助后过渡金属氢化物还原 CO(2)。
影响因子：
2.8
作者：
Miller,AlexanderJM;Labinger,JayA;Bercaw,JohnE
通讯作者：
Bercaw,JohnE
影响因子：
8.4
作者：
Wesselbaum S;Moha V;Meuresch M;Brosinski S;Thenert KM;Kothe J;Stein TV;Englert U;Hölscher M;Klankermayer J;Leitner W
通讯作者：
Leitner W