geometry. Complexes of type [Ir(NHC)(CO)2Cl] [NHC = 1,3-diisopropyl(5,6-dimethyl)benzimidazol-2-ylidene] 3 were also synthesized to compare σ-donor/π-acceptor strength of NHC ligands. Transfer hydrogenation (TH) reactions of various aldehydes and ketones have been studied using complexes 2a and 2b as catalysts. The 5,6-dimethyl substituted iridium complex (2b) showed the highest catalytic activity for the
两个新的[Ir(NHC)(COD)Cl](NHC = N-杂环卡宾; COD =
1,5-环辛二烯)
铱络合物(2a,b)是通过[Ir(COD)Cl] 2与原位制备的NHC-Ag卡宾转移剂在
二氯甲烷在环境温度下。它们已通过1 H,13 C NMR和元素分析充分表征。对2a和2b的单晶进行的X射线衍射研究证实了正方形的平面几何形状。还合成了[Ir(NHC)(CO)2 Cl]类型的配合物[NHC = 1,3-
二异丙基(5,6-二甲基)
苯并咪唑-2-亚烷基] 3,以比较σ-供体/π-受体强度。 NHC
配体。已经使用络合物2a和2b作为催化剂研究了各种醛和酮的转移氢化(TH)反应。5,6-二甲基取代的
铱配合物(2b)对TH反应显示出最高的催化活性。