Synthetic, structural and spectroscopic studies of (pseudo)halo(1,3-di-tert-butylimidazol-2-ylidine)gold complexes
作者:Murray V. Baker、Peter J. Barnard、Simon K. Brayshaw、James L. Hickey、Brian W. Skelton、Allan H. White
DOI:10.1039/b412540a
日期:——
A series of (pseudo)halo(1,3-di-tert-butylimidazol-2-ylidine)gold complexes [(But2Im)AuX]
(X = Cl, Br, I, CN, N3, NCO, SCN, SeCN, ONO2, OCOCH3, CH3) have been synthesized and characterised spectroscopically and structurally. 13C NMR chemical shifts for the carbene carbon vary widely with differing ancillary anion, correlating well with the σ-donor ability of the latter and with the M–C(carbene) bond distance. These results reinforce the notion that N-heterocyclic carbene ligands are primarily σ-donor ligands with little π-acceptor ability.
我们合成了一系列(假)卤代(1,3-二叔丁基咪唑-2-基啶)金配合物 [(But2Im)AuX] (X = Cl、Br、I、CN、N3、NCO、SCN、SeCN、ONO2、OCOCH3、CH3),并从光谱和结构上对其进行了表征。碳烯碳的 13C NMR 化学位移随辅助阴离子的不同而变化很大,与后者的 σ 供体能力和 M-C(碳烯)键距离密切相关。这些结果加强了这样一种观点,即 N-杂环碳烯配体主要是σ-供体配体,几乎没有π-受体能力。