Heterogenised N-heterocyclic carbene complexes: synthesis, characterisation and application for hydroformylation and C–C bond formation reactions
作者:Sarim Dastgir、Karl S. Coleman、Malcolm L. H. Green
DOI:10.1039/c0dt00760a
日期:——
The imidazolium salts: 1-mesityl-3-(3-trimethoxysilylpropyl)imidazolium iodide and 1-tert-butyl-3-(3-trimethoxysilylpropyl)imidazolium iodide, abbreviated as (tmpMes)HI (3a) and (tmptBu)HI (3b), respectively, have been synthesised. The palladium(II) complexes (η3-C3H5) (tmpMes)PdCl (5a) and (η3-C3H5)(tmptBu)PdCl (5b), rhodium(I) and iridium(I) complexes (η4-1,5-COD) (tmpMes)MCl, M = Rh (6a), Ir (7a) and (η4-1,5-COD)(tmptBu)MCl, where M = Rh (6b), Ir (7b), were synthesised by silver transmetallation reactions using the silver(I) complexes (tmpMes)AgI (4a) and (tmptBu)AgI (4b). The iridium complex 7b has been structurally characterised. The Pd(II) and Rh(I) complexes have been immobilised by attachment to chemically modified MCM-41. The immobilised palladium(II) materials have been tested as recyclable catalysts for Suzuki type CâC bond formation reactions in water and the immobilised rhodium(I) materials have been examined for their catalytic ability for the hydroformylation of 1-octene.
合成了咪唑鎓盐:1-梅斯基尔-3-(3-三甲氧基硅基丙基)咪唑鎓碘化物和1-叔丁基-3-(3-三甲氧基硅基丙基)咪唑鎓碘化物,分别简写为(tmpMes)HI (3a)和(tmptBu)HI (3b)。通过银转金属反应,使用银(I)络合物(tmpMes)AgI (4a)和(tmptBu)AgI (4b),合成了钯(II)络合物(η³-C₃H₅)(tmpMes)PdCl (5a)和(η³-C₃H₅)(tmptBu)PdCl (5b),以及铑(I)和铱(I)络合物(η⁴-1,5-COD)(tmpMes)MCl,M = Rh (6a), Ir (7a)和(η⁴-1,5-COD)(tmptBu)MCl,M = Rh (6b), Ir (7b)。铱络合物7b已进行结构表征。钯(II)和铑(I)络合物通过与化学改性的MCM-41相结合而被固定化。固定化的钯(II)材料已作为可回收催化剂在水中进行铃木类型的C–C键形成反应进行了测试,而固定化的铑(I)材料则用于1-辛烯的羟基甲基化反应的催化能力研究。