Proton exchange and base-catalysed hydrolysis of some trans- and cis-dichloro(1,4,8,11-tetra-azacyclotetradecane) complexes of chromium(III), ruthenium(III), and rhodium(III)
作者:Martha E. Sosa、Martin L. Tobe
DOI:10.1039/dt9860000427
日期:——
cis-[MRRRR(SSSS)-cyclam}Cl2]+(M = Cr or Rh)(cyclam = 1,4,8,11-tetra-azacyclotetradecane) have been estimated from the proton exchange (k1) and base hydrolysis (kOH) rate constants. All complexes are considerably less reactive towards base hydrolysis than the analogous CoIII species. The lower reactivity of CrIII is due to a lowering of k1 and k2/k–1 by similar amounts, while that of RhIII arises mainly
反式-[M RSSR -cyclam} Cl 2 ] +(M = Cr,Ru或Rh)的酰胺共轭碱的溶剂分解(k 2)和质子化(k –1)的速率常数之比和顺- [M RRRR(SSSS)-cyclam}氯2 ] +(M = Cr或RH)(cyclam = 1,4,8,11-四azacyclotetradecane)从质子交换已被估计(ķ 1)和碱水解(k OH)速率常数。与类似的Co III相比,所有配合物对碱水解的反应性均显着降低。物种。Cr III的较低反应性是由于k 1和k 2 / k –1降低了相似的量,而Rh III的反应性主要是由于顺式异构体中k 2 / k –1的大幅降低而引起的。类似的还原的ķ 2 / ķ 1再加上一个大的降低ķ 1占的非常低的反应性的反式异构体。k 2 / k –1大大减少为反式的Ru III配合物是通过在一大的增加补偿ķ 1。