Institut für Anorganische Chemie, Johannes Kepler Universität Linz, Austria.
Dalton Trans. 2011 Oct 14;40(38):9899-910. doi: 10.1039/c1dt11175b. Epub 2011 Aug 30.
Gold(I) complexes bearing N-heterocyclic carbenes (NHC) of the type (NHC)AuBr (3a/3b) [NHC = 1-methyl-3-benzylimidazol-2-ylidene (= MeBnIm), and 1,3-dibenzylimidazol-2-ylidene (= Bn(2)Im)] are prepared by transmetallation reactions of (tht)AuBr (tht = tetrahydrothiophene) and (NHC)AgBr (2a/2b). The homoleptic, ionic complexes [(NHC)(2)Au]Br (6a/6b) are synthesized by the reaction with free carbene. Successive oxidation of 3a/3b and 6a/6b with bromine gave the respective (NHC)AuBr(3) (4a/4b) and [(NHC)(2)AuBr(2)]Br (7a/7b) in good overall yields as yellow powders. All complexes were characterized by NMR spectroscopy, mass spectrometry, elemental analysis and single crystal X-ray diffraction. Reactions of the Au(III) complexes towards anionic ligands like carboxylates, phenolates and thiophenolates were investigated and result in a complete or partial reduction to a Au(I) complex. Irradiation of the Au(III) complexes with UV light yield the Au(I) congeners in a clean photo-reaction.
金（I）配合物，带有 N-杂环卡宾（NHC）的类型（NHC）AuBr（3a/3b）[NHC = 1-甲基-3-苄基咪唑-2-亚基（= MeBnIm）和 1,3-二苄基咪唑-2-亚基（= Bn（2）Im）]，通过（tht）AuBr（tht =四氢噻吩）和（NHC）AgBr（2a/2b）的转金属反应制备。均相，离子配合物[(NHC)（2）Au]Br（6a/6b）通过与游离卡宾反应合成。3a/3b 和 6a/6b 的连续氧化与溴反应，以良好的总收率得到相应的（NHC）AuBr（3）（4a/4b）和[(NHC)（2）AuBr（2）]Br（7a/7b），为黄色粉末。所有配合物均通过 NMR 光谱，质谱，元素分析和单晶 X 射线衍射进行了表征。研究了 Au（III）配合物与羧酸根，酚盐和硫酚盐等阴离子配体的反应，导致完全或部分还原为 Au（I）配合物。用紫外线照射 Au（III）配合物可以在干净的光反应中生成 Au（I）同系物。
