Triarylphosphine, hydride, and ethylene complexes or rhodium(I) chloride
Triarylphosphine, hydride, and ethylene complexes or rhodium(I) chloride
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三芳基膦、氢化物和乙烯络合物或氯化铑(I)
DOI：
10.1021/ja00816a018
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发表时间：
1974
影响因子：
15
通讯作者：
J. Jesson
中科院分区：
文献类型：
--
作者：
C. A. Tolman;P. Meakin;D. Lindner;J. Jesson
结合分子量、~（31）P、~（13）C、核磁共振、红外光谱和分光光度测量，对RlffCl、三芳基膦[PPh_3或P（p-甲苯基）_3]、H_2、乙烯和环己烯的混合溶液中的反应进行了物理研究，确定了反应的物种、速率和平衡。RhClL 3复合物不会解离为RhClL 2至光谱可检测的程度，但与氯桥二聚体[RhClL 2] 2处于平衡。二聚体与H2反应形成H2 [RhClL 2] 2，并且容易被L或乙烯裂解，但不被环己烯裂解，形成RhClL 3或（C2 H4）RhClL 2。二聚体本身是一种良好的均相加氢催化剂。一个物种的组成RhClL 2，而不是光谱检测，必须假设为动力学中间体，以解释动力学的H2反应与溶液的RhClL 3或H2与环己烯的溶液中的[RhClL 2] 2。
Physical studies, combining molecular weights, 31P, I3C, and nmr, infrared, and spectrophotometric measurements, have been made to define the species and rates and equilibria of reactions in solutions con-taining mixtures of RlffCl, triarylphosphines [PPh3 or P (p-tolyl) 3], H2, ethylene, and cyclohexene. The RhClL3 complexes do not dissociate to RhClL2 to a spectroscopically detectable extent but are in equilibrium with the chlorine bridged dimer [RhClL2] 2. The dimer reacts with H2 to form H2 [RhClL2] 2 and is readily cleaved by L or ethylene, but not cyclohexene, to form RhClL3 or (C2H4) RhClL2. The dimer itself is a good homogeneous hydro-genation catalyst. A species of composition RhClL2, while not spectroscopically detectable, must be postulated as a kinetic intermediate in order to explain the kinetics of H2 reaction with solutions of RhClL3 or of H2 with cyclohexene in solutions of [RhClL2] 2.