Ring-Expanded N-Heterocyclic Carbene Complexes of Ruthenium

被引：32

作者：

Armstrong, Robert ^{[1
]}

Ecott, Christopher ^{[1
]}

Mas-Marza, Elena ^{[1
]}

Page, Michael J. ^{[1
]}

Mahon, Mary F. ^{[1
]}

Whittlesey, Michael K. ^{[1
]}

机构：

[1] Univ Bath, Dept Chem, Bath BA2 7AY, Avon, England

来源：

ORGANOMETALLICS | 2010年 / 29卷 / 04期

基金：

英国工程与自然科学研究理事会;

关键词：

C-H ACTIVATION; TRANSITION-METAL-COMPLEXES; OLEFIN METATHESIS CATALYST; BOND ACTIVATION; NUCLEOPHILIC CARBENES; 14-ELECTRON RH(III); IRIDIUM COMPLEXES; HYDRIDE COMPLEXES; X BOND; LIGANDS;

D O I：

10.1021/om901044u

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

The six-membered N-heterocyclic carbene 1,3-bis(2,4,6-trimethylphenyl)-3,4,5,6-tetrahydropyrimidin-2-ylidene (6-Mes) reacts with Ru(PPh3)(3)(CO)HF to afford Ru(6-Mes)(PPh3)(CO)HF (1), which is converted to the five-coordinate C-H activated carbene complex Ru(6-Mes)'(PPh3)(CO)H (2) upon treatment with Et3SiH. The hydride chloride precursor Ru(PPh3)(3)(CO)HCl affords a mixture of products with 6-Mes, but reacts cleanly with 1,3-bis(isopropyl)-3,4,5,6-tetrahydropyrimidin-2-ylidene (6-Pr-i) to give the six-coordinate activated complex Ru(6-Pr-i)'(PPh3)(2)(CO)H (3a), in which the hydride is trans to the methylene arm of the activated NHC. This complex isomerizes in solution with Delta H double dagger and AS double dagger values of 98.2 +/- 4.6 kJ mol(-1) and 15.5 +/- 14.5 J mol(-1) K-1. The major product from the isomerization, 3b, in which the hydride ligand is trans to carbene, can be made directly by reaction of 6-'Pr with Ru(PPh3)(3)(CO)H-2.

引用

页码：991 / 997

页数：7

共 84 条

[1] Coordinatively unsaturated hydridoruthenium(II) complexes of N-heterocyclic carbenes [J].