Wang Chunhong, Xiang Li, Leng Xuebing, Chen Yaofeng
State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, People's Republic of China.
Dalton Trans. 2017 Jan 24;46(4):1218-1227. doi: 10.1039/c6dt04441g.
The reactions of rare-earth metal benzyl complexes supported by silicon-bridged boratabenzene fluorenyl ligands with PhSiH in toluene gave the corresponding dinuclear hydrides [{μ-[MeSi(CH)(CHBNEt)]}Ln(μ-H)(THF)] (3-Ln; Ln = La, Nd, Gd), wherein the rare-earth metal ions are linked by both silicon-bridged boratabenzene fluorenyl ligands and hydrido ligands. The reactivity of these hydrides toward unsaturated substrates was studied. Among these, alkynides [{μ-[MeSi(CH)(CHBNEt)]}Ln(μ-CCPh)] (4-Ln; Ln = La, Nd) were obtained via the σ-bond metathesis reaction, when 3-Ln (Ln = La, Nd) was treated with phenylacetylene. While reacting with 3-hexyne, the mono-addition product {μ-[MeSi(CH)(CHBNEt)]}Ln[μ-C(Et)[double bond, length as m-dash]C(H)Et] (5-Ln; Ln = La, Nd) was formed. Further investigations on the reactivity of 3-La displayed that benzonitrile and tert-butyl isonitrile readily inserted into the La-H bonds, affording an azomethine complex [{μ-[MeSi(CH)(CHBNEt)]}La{μ-N[double bond, length as m-dash]C(H)Ph}] (6-La) and an N-tert-butylformimidoyl complex [{μ-[MeSi(CH)(CHBNEt)]}La{μ,η-C(H)[double bond, length as m-dash]NBu}] (7-La), respectively. The reaction with N,N'-diisopropylcarbodiimide at room temperature or at 75 °C gave a dimeric complex {μ-[MeSi(CH)(CHBNEt)]}La[μ-N(Pr)CHN(Pr)] (8-La) or a monomeric complex [MeSi(CH)(CHBNEt)]La[N(Pr)CHN(Pr)] (9-La), respectively.
由硅桥联硼杂苯芴基配体支撑的稀土金属苄基配合物与甲苯中的PhSiH反应，生成了相应的双核氢化物[{μ-[MeSi(CH)(CHBNEt)]}Ln(μ-H)(THF)] (3-Ln；Ln = La、Nd、Gd)，其中稀土金属离子通过硅桥联硼杂苯芴基配体和氢化物配体相连。研究了这些氢化物对不饱和底物的反应活性。其中，当用苯乙炔处理3-Ln (Ln = La、Nd)时，通过σ键复分解反应得到了炔化物[{μ-[MeSi(CH)(CHBNEt)]}Ln(μ-CCPh)] (4-Ln；Ln = La、Nd)。与3-己炔反应时，形成了单加成产物{μ-[MeSi(CH)(CHBNEt)]}Ln[μ-C(Et)[双键，长度为m破折号]C(H)Et] (5-Ln；Ln = La、Nd)。对3-La反应活性的进一步研究表明，苯甲腈和叔丁基异腈很容易插入到La-H键中，分别得到一个甲亚胺配合物[{μ-[MeSi(CH)(CHBNEt)]}La{μ-N[双键，长度为m破折号]C(H)Ph}] (6-La)和一个N-叔丁基甲脒基配合物[{μ-[MeSi(CH)(CHBNEt)]}La{μ,η-C(H)[双键，长度为m破折号]NBu}] (7-La)。在室温或75°C下与N,N'-二异丙基碳二亚胺反应，分别得到一个二聚配合物{μ-[MeSi(CH)(CHBNEt)]}La[μ-N(Pr)CHN(Pr)] (8-La)或一个单体配合物[MeSi(CH)(CHBNEt)]La[N(Pr)CHN(Pr)] (9-La)。
