A family of alkenyl-functionalized N-heterocyclic-carbene–iridium(I) complexes has been synthesized, providing a series of mono-coordinated, bis-chelate and pinceralkenyl-NHC species. Olefin coordination is highly influenced by the nature of the substituents on the NHC ring, and on the length of the alkenyl branch. A fluxional process involving coordination/decoordination of the olefin in bis-allyl-NHC complexes has been studied, and the activation parameters have been determined by means of VT-NMR spectroscopy. The mono-coordinated complexes are highly active in the hydrosilylation of terminal alkynes, showing high selectivity for the Z-isomers, with no α-isomers or dehydrogenative silylation processes being observed. The molecular structures reported that are representative of the species have been determined by means of X-ray crystallography.
我们合成了一系列烯基官能化的 N-杂环碳-
铱(I)络合物,提供了一系列单配位、双螯合和钳烯基-NHC 种类。烯烃配位受 NHC 环上取代基的性质和烯烃支长度的影响很大。我们研究了
双烯丙基-NHC 复合物中烯烃配位/脱配位的通量过程,并通过 VT-NMR 光谱测定了活化参数。单配位配合物在末端
炔烃的氢化
硅烷化过程中具有很高的活性,对 Z-异构体具有很高的选择性,没有观察到 α-异构体或脱氢
硅烷化过程。报告中具有代表性的分子结构是通过 X 射线晶体学确定的。