1,2-metallotropic shifts in tricarbonylrhenium(I) complexes of pyridazine (pydz): A dynamic NMR investigation of the effects of cis-chelating ligands

被引：10

作者：

Abel, EW ^{[1
]}

Heard, PJ ^{[1
]}

Orrell, KG ^{[1
]}

机构：

[1] UNIV EXETER,DEPT CHEM,EXETER EX4 4QD,DEVON,ENGLAND

来源：

INORGANICA CHIMICA ACTA | 1997年 / 255卷 / 01期

关键词：

rhenium complexes; chelate ligand complexes; fluxional pyridazine complexes; dynamic NMR;

D O I：

10.1016/S0020-1693(96)05339-X

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

Complexes of general formula fac-[Re(CO)(3)(L-L)(pydz)][BF4] (L-L=neutral bidentate chelate ligand; pydz=pyridazine) were prepared in high yield from fac-[ReBr(CO)(3)(L-L)]. The pyridazine ligand coordinates to the metal moiety in a monodentate fashion, and undergoes a facile intramolecular 1,2-Re-N shift. The kinetics of the 1,2-metallotropic shift were measured by either one-dimensional NMR bandshape analysis or two-dimensional exchange spectroscopy. The free energies of activation, Delta G(not equal) (298 K), were found to be dependent on the nature of the chelate ligand, and were in the range 77-87 kl mol(-1). The origins of the chelate ligand effects are discussed.

引用

页码：65 / 71

页数：7

共 22 条

[1] 2,2' - 6',2''-TERPYRIDINE (TERPY) ACTING AS A FLUXIONAL BIDENTATE LIGAND .2. RHENIUM CARBONYL HALIDE-COMPLEXES, FAC-[REX(CO)3(TERPY)] (X = CL, BR OR I) - NMR-STUDIES OF THEIR SOLUTION DYNAMICS, SYNTHESIS OF CIS-[REBR(CO)2(TERPY)] AND THE CRYSTAL-STRUCTURE OF [REBR(CO)3(TERPY)] [J].