Synthesis and aquation kinetics of the cis-dichloro- and three diastereoisomeric trans-dichloro-complexes of cobalt(III) with the macrocyclic ligand C-rac-5,12-dimethyl-1,4,8,11-tetra-azacyclotetradecane
作者:Robert W. Hay、Donald A. House、Ramesh Bembi
DOI:10.1039/dt9840001927
日期:——
The synthesis and characterisation of cis-[CoCl2L]Cl and three diastereoisomeric trans-[CoCl2L]ClO4 complexes [designated (B), (C), and (D)] are described (L = C-rac-5,12-dimethyl-1,4,8,11-tetra-azacyclotetradecane). Ten diastereoisomeric trans-[CoCl2L]+ complexes are in principle possible. Isomer (B) is pale green, is aquated without isomerisation (kaq.25= 4.5 × 10–5 s–1), and has the trans III (RSSR)
的合成和表征顺- [氯化钴2 L] Cl和3非对映异构的反式- [氯化钴2 L] CLO 4配合物[指定(B),(C),和(d)]中描述了(L = C-外消旋- 5,12-二甲基-1,4,8,11-四氮杂环十四烷)。原则上可能有十种非对映异构体反式-[CoCl 2 L] +配合物。异构体(B)为淡绿色,无需异构化aquated(ķ水溶液25 = 4.5×10 -5小号-1),并具有反式III(RSSR)手性氮中心的构型,带有一个赤道和一个轴向甲基取代基(通过1 H nmr测量确认)。该异构体可与“水合惰性” [CoCl 2-(cyclam)] +异构体相当(cyclam = 1,4,8,11-四氮杂环十四烷)。异构体(C)是明亮的绿色,比异构体(B)aquated更快速地(ķ水溶液25 = 6.5×10 -4小号-1),得到结构的绿色chloroaqua络合物指示保留,并可以具有与配置两个