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1.
2.
Dinuclear Silylene Bridged Cyclopentadienylrhodiumbis(ethene) Complexes, Photochemical Reaction with Benzene Derivatives, and Selective Inclusion of Methylcyclopentane into the Crystal Lattice of [Me2Si{3-But-C5H3Rh(C2H4)2}2] By reaction of [{(C2H4)2RhCl}2] with Na2[Me2Si(C5H4)2] or with Li2[Me2Si(3-But-C5H3)2] in THF the dinuclear silylene bridged complexes [Me2Si{C5H4Rh(C2H4)2}2] 1 and [Me2Si{3-But-C5H3Rh(C2H4)2}2] 2 , respectively, were synthesized. Due to the asymmetric substitution of the five-membered rings and their hindered rotation around the Si? C axes, 2 is formed as three isomers. The X-ray structure analysis of 2 obtained from hexane reveals the selective inclusion of methylcyclopentane, the content of which in the solvent is about 17%, into the crystal lattice. UV irradiation of 1 in hexane in the presence of benzene causes elimination of the ethene ligands yielding the μ-η3:η3 benzene complex [Me2Si(C5H4Rh2)2C6H6] which cannot be separated from unreacted 1 . However, separation is possible in case of the hexamethylbenzene compound 4 analogous with 3 . 相似文献
3.
Garth R. Giesbrecht Gavin E. Collis John C. Gordon David L. Clark Brian L. Scott Ned J. Hardman 《Journal of organometallic chemistry》2004,689(13):2177-2185
Use of the bulky cyclopentadienyl ligand [η5-C5H2(SiMe3)3-1,2,4]− (Cp?) allows for the isolation of monomeric, mono-ring lanthanide species. As previously reported, (Cp?)K reacts with LaI3(THF)4 (THF=tetrahydrofuran) in THF/pyridine to form the mono-ring complex (Cp?)LaI2(py)3 (1) (py=pyridine); a minor product of this reaction is the bis-ring species (Cp?)2LaI(py) (2). The solid state structure of 2 reveals a monomeric compound containing a pseudo-tetrahedral metal center exhibiting no unusual intramolecular contacts. Addition of one equiv of KNHAr (Ar=2,6-iPr2C6H3) to complex 1 in THF generates the mono-anilido compound (Cp?)LaI(NHAr)(THF)2 (3), which may be converted to the more stable pyridine adduct (Cp?)LaI(NHAr)(py)2 (4) by the addition of pyridine to 3. An X-ray crystal structure of 3 indicated a trigonal bipyramidal metal center with the anilido group oriented trans to the iodide atom (N1-La1-I1=123.1(3)°). A structural study on the bis-pyridine adduct 4 revealed a similar Cs-symmetric structure with a slightly increased Nanilido-La-I angle of 132.1(2)°. Addition of KNHAr to the di-iodo bipyridine adduct (Cp?)LaI2(bipy)(py) (5), in which the two iodide atoms are cis-disposed, yields the mono-anilido complex (Cp?)LaI(NHAr)(bipy)(py) (6) (bipy=2,2′-bipyridine); this compound may also be prepared by the addition of bipy to (Cp?)LaI(NHAr)(py)2 (4). An X-ray diffraction study shows that the lanthanum center in 6 is octahedrally coordinated by a Cp? ring, an iodide, an anilido group, a pyridine molecule and two nitrogens of a bipy molecule. In this case, the anilido moiety and the iodide ligand are arranged in a cis fashion (Nanilido-La-I=111.2(2)°), resulting in a complex with C1 symmetry. Both (Cp?)LaI(NHAr)(py)2 (4) and (Cp?)LaI(NHAr)(bipy)(py) (6) are inactive as catalysts for the hydroamination/cyclization of 2-amino-hex-5-ene. 相似文献
4.
Tetramethyldisilane-1,2-diyl bridged Dicyclopentadienyl and Diindenyl Metal Dichlorides of the Group 4 Metals – Crystal Structure of Dicyclopentadienyl and diindenyl metal dichlorides of the type Cp′? SiMe2SiMe2? Cp′MCl2 (Cp′ = C5H4, M = Ti ( 1 ), Zr ( 2 ), Hf ( 3 ); Cp′ = C9H7, M = Zr ( 4 ), Hf ( 5 )) were synthesized and characterized by means of their 1H, 13C, 29Si-n.m.r., MS, and IR spectra. The crystal structure of 2 was determined. 相似文献
5.
茂基稀土胺化物(MeCp)2YbNPh2(THF)与异氰酸正己酯(n-HexylNCO)按11摩尔比反应, 分离出产物{(MeC5H4)2Yb[OC(NPh2)N(n-hexyl)]}2. 产物经元素分析和核磁共振表征, 并测定了其晶体结构. 配合物属三斜晶系, R-3空间群, 晶胞参数为a=2.9533(11) nm, b=2.9533(11) nm, c=1.5873(6) nm, V=11.9896(80) nm3, Z=9, Dc=1.562 mg·m-3, μ=3.536 mm-1 (Mo Kα), F(000)=5670, R=0.034, Rw=0.064. 该化合物具有二个对称氧桥的双分子结构, 并存在着由氮原子向中心金属镱分子内配位而形成的三环骨架, 中心金属镱的配位数是九, 整个分子呈中心对称. 相似文献
6.
通过1-环庚烯基锂与6,6-二烷基富烯发生环外双键的加成反应形成的大取代茂锂试剂与MCl4(M=Ti,Zr)反应,合成了12个含或不含手性碳的大位阻取代茂金属有机化合物,并研究了它们的1HNMR,EIMS和IR. 相似文献
7.
8.
1,2-Diphenyl-1,2-dimethyldisilanylene-bridged bis-cyclopentadienyl complex[η~5,η~5-C_5H_4PhMeSiSiMePh-C_5H_4]Fe_2(CO)_2(μ-CO)_2(1)was synthesized by a modified procedure,from which the trans-isomer 1b that was pre-viously difficult to obtain has been isolated for the first time.More interestingly,two new regio-isomers[η~5,η~5C_5H_4SiMe(SiMePh_2)C_5H_4]Fe_2(CO)_2(μ-CO)_2(2)and [η~5,η~5-C_5H_4Me_2SiSiPh_2C_5H_4]Fe_2(CO)_2(μ-CO)_2(3)were occa-sionally obtained during above process,the novel structures of which opened up new options for further study ofthis type of Si—Si bond-containing transition metal complexes.The molecular structure of 2 has been determinedby the X-ray diffraction method. 相似文献
9.
A. A. Bezrukova V. S. Khandkarova P. V. Petrovskii A. Z. Rubezhov Ya. S. Vygodskii K. P. Butin T. V. Magdesieva G. A. Pirogova 《Russian Chemical Bulletin》1995,44(5):941-945
Binuclear RhIII and RuII complexes of the [M1-CN-M2]+BF
4
–
(M1 and/or M2 are (5-Cp)(3-C3H5)Rh and (6-C6H6)(3-C3H5)Ru) type, heteronuclear organometallic compound (5-Cp)(3-C3H5)RhCNPd(3-C3H5)Cl, and mononuclear RhIII and RuII complexes [(3-C3H5)LM(MeCN)]+
BF4
–
(M = Rh, L = 5-Cp; M = Ru, L = 6-C6H6) were synthesized. An electrochemical study of these compounds in solutions demonstrates that the bond between the bridged CN ligand and the metal atoms is rather strong, and there is no dissociation into mononuclear fragments in solutions. The kinetics of the reaction of [(5-Cp)(3-C3H5)Rh(MeCN)]+
BF4
–
with halide ions was studied by electrochemical methods. The ligand exchange proceeds by a bimolecular dissociative-exchange mechanism.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 968–973, May, 1995. 相似文献
10.
Bis(cyclopentadienyl)methane-bridged Dinuclear Complexes, V[1]. – Heteronuclear Co/Rh-, Co/Ir-, Rh/Ir-, and Ti/Ir Complexes with the Bis(cyclopentadienyl)methane Dianion as Bridging Ligand* The lithium and sodium salts of the [C5H5CH2C5H4]- anion, 1 and 2 , react with [Co(CO)4I], [Rh(CO)2Cl]2, and [Ir(CO)3Cl]n to give predominantly the mononuclear complexes [(C5H5-CH2C5H4)M(CO)2] ( 3, 5, 7 ) together with small amounts of the dinuclear compounds [CH2(C5H4)2][M(CO)2]2 ( 4, 6, 8 ). The 1H- and 13C-NMR spectra of 3, 5 , and 7 prove that the CH2C5H5 substituent is linked to the π-bonded ring in two isomeric forms. Metalation of 5 and 7 with nBuLi affords the lithiated derivatives 9 and 10 from which on reaction with [Co(CO)4I], [Rh(CO)2Cl]2, and [C5H5TiCl3] the heteronuclear complexes [CH2(C5H4)2][M(CO)2][M′(CO)2] ( 11–13 ) and [CH2(C5H4)2]-[Ir(CO)2][C5H5TiCl2] ( 17 ) are obtained. Photolysis of 11 and 12 leads almost quantitatively to the formation of the CO-bridged compounds [CH2(C5H4)2][M(CO)(μ-CO)M′(CO)] ( 14, 15 ). According to an X-ray crystal structure analysis the Co/Rh complex 14 is isostructural to [CH2(C5H4)2][Rh2(CO)2(μ-CO)] ( 16 ). 相似文献