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用茂钛配合物高效、高选择性催化4-乙烯基环己烯的异构化 总被引:1,自引:0,他引:1
The catalytic species [Cp2TiH], formed in situ from the reaction of titanocene dichloride with Grignard reagents having a β-H, was found to be a very effective catalytic system for isomerization of diolefin[1~3]. Based on our previous work[3], the titanium-catalyzed isomerization of 4-vinyl-cyclohexene (VCH) was studied in some detail. In this communication, we report the use of various substituted titanocene and polymer-supported titanocene complexes with Grignard reagents as catalyst for the isomerization of VCH. It was reported that base-catalyzed isomerization of VCH formed a very complicated mixture with 60 % conversion[4]. 相似文献
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采用“原位反应”的方法,研究了配合物Pt(PMe3)2(CO)2和Pt(diphos)(CO)2(diphos:1,2-二(二特丁基膦)乙烷,即d(t-Bu)Pe,1,2-二(二环己基膦)乙烷,即dCyhPe;1,2-二(二环戊基膦)乙烷,即dCypPe;1,2-二(苯基特丁基膦)乙烷,即Ph(t-Bu)Pe)在室温和压下对苯的光羰化反应性能,得到了预期的反应产物苯甲醛和苯甲醇。它们均经色-质分析 相似文献
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某些氨基取代环戊二烯配合物催化1,5-己二烯的高选择性环化 总被引:2,自引:0,他引:2
We have interested for some years in studying organic reactions catalyzed by (RCp)2TiCl2/i-C3H7MgX, specially isomerization of non-conjugated dienes[1,2]. Titanocene complexes are also effective for some cyclization reactions[3]. In the case of isomerization of 1,5-hexadiene (HD), such catalysts usually result in a mixture of 1,4-hexadiene, 1,3-hexadiene, 2,4-hexadiene, methylenecyclopentane and methylcyclopentene. Our previous results showed that the product distribution largely depends on the characteristics of the substituents on cyclopentadienyl (Cp) ring[2]. 相似文献
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配位催化有催化剂和产物不易分离、溶剂污染环境等问题.而使用水溶性催化体系是克服这些缺点的有效方法之一,并且催化剂还可以循环使用.1984年德国鲁尔化学工业公司用水溶性铑-膦配合物为催化丙烯氢甲酰化生产取得了成功.在众多的水溶性配体中,三-间磺酸钠-三苯基膦[trisodi- 相似文献
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1 INTRODUCTIONCyclopentadienylcomplexeshavebeenintensivelystudiedfortheirrichchemicalandcatalyticproperties〔1〕.Ithasbeenwellestablishedthatthereplacementofanη5-cyclopentadienylligandbyanη5-pentamethylcyclopentadienylligandintransitionmetalcomplexesre… 相似文献
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Wei-xia Tu Han-fan Liu 《高分子科学》2005,(5):487-495
Polymer-stabilized platinum/ruthenium bimetallic colloids (Pt/Ru) were synthesized by polyol reduction with microwave irradiation and characterized by TEM and XPS. The colloidal nanoparticles have small and narrow size distributions. Catalytic performance of the Pt/Ru colloidal catalysts was investigated on the selective hydrogenation of crontonaldehyde (CRAL). A suitable amount of the added metal ions and base can improve the selectivity of CRAL to crotylalcohol (CROL) remarkably. The catalytic activity and the selectivity are dependent on the compositions of bimetallic colloids. Thereinto, PVP-stabilized 9Pt/1Ru colloid with a molar ratio of metals Pt:Ru = 9:1 shows the highest catalytic selectivity 77.3% to CROL at 333 K under 4.0 MPa of hydrogen. 相似文献
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《Journal of Coordination Chemistry》2012,65(1-2):95-106
Abstract A cobalt(III) complex containing (R)-2-methylaziridine (R-meaz), [Co(R-meaz)(NH3)5]3+, was prepared and the two diastereomers arising from the presence of the chiral nitrogen atom (N(R) and N(S)) were separated by column chromatography. Molecular mechanics calculations estimated the N(R)-isomer to be more stable. This result was supported by the x-ray structure determination of the more abundant (ca. 94%) isomer, N(R)-[Co(R-meaz)(NH3)5]Br3H2O. Crystal data: monoclinic, P21, a = 7.357(1), b = 9.780(1), c = 10.426(1) Å, μ = 93.58(1)°, V= 748.7(3) Å3, Z= 2. Kinetic studies of isomerization (epimerization) between the two isomers revealed that inversion at the nitrogen center was very slow (5 × 10?2 M?1 S?1at 25 °C). The small rate constant seems to be related to the strained three-membered structure of the meaz ligand. The reaction of Na3[Co(N02)6] and R-meaz yielded a complex containing two dimerized R-meaz chelates, trans-[Co(NO2)2(di-R-meaz)2] (di-R-meaz =RR)-α,2-dimethyl-l-aziridineethanamine). The crystal strucrure of trans-[Co(NO2)2 (di-R-meaz)2]C1O4H2O was established by x-ray crystallography. Crystal data: orthorhombic, P212121, a = 11.784(6), b = 21.023(9), c = 8.608(7) Å, V = 2133(2) Å3, Z = 4. 相似文献
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本文评述了饱和烃C—H键活化的最近进展,从配位催化和量子化学的观点,推断了饱和烃C—H键活化及其配位催化反应的机理:首先是它的非定域轨道里的电子对配位在催化剂中心金属的d_z~2/d_■~2-■~2混合轨道上,然后电子从催化剂的HOMO流向底物的LUMO,发生氧化加成反应,生成烷基金属氢化物过渡态,最后经插入反应、还原消除反应,完成整个催化循环。此外,还展望了未来的发展前景。 相似文献
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Polymer-supported ruthenium complexes ■-Phen-Ru-①,■-Phen-Ru-②,■-Phen-Ru-③,■-Phen-Ru-④, ■-Phen-Ru-⑤,■-Phen-Ru-⑥and ■-Phen-Ru-⑦were prepared using aminomethyl polystyrenes of different morphological structures as supports.A variety of alcohols were oxidized efficiently into the corresponding ketones, carboxylic acids or aldehydes with iodosylbenzene (PhIO) catalyzed by aminomethyl polystyrene-supported ruthenium complexes under mild reaction conditions in acetonitrile.The influences of morphological struct... 相似文献