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有机硅聚合物负载膦铂,膦铑络合物的合成及催化硅氢化性能 总被引:3,自引:1,他引:3
从p-氯烯丙苯出发,通过相继地与三甲氧基硅烷进行硅氢加成、二苯膦钾膦化、气相法二氧化硅固载化,再与氯亚铂酸钾或三氯化铑反应,合成了聚γ-(p-二苯膦苯基)丙基硅氧烷铂、铑络合物。两者对烯烃与三乙氧基硅烷的硅氢加成反应具有良好的催化活性。 相似文献
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聚γ—(β—氰乙硫基)丙基硅氧烷铂配合物的合成与催化性能 总被引:2,自引:0,他引:2
γ-巯丙基三乙氧基硅烷与丙烯腈反应,得到γ-(β-氰乙硫基)丙基三乙氧基硅烷.后者经气相法二氧化硅固载,再与氯亚铂酸钾反应,合成了聚γ-(β-氰乙硫基)丙基硅氧烷铂配合物.研究了该铂配合物对不饱和烃与三乙氧基硅烷的硅氢加成反应的催化特性. 相似文献
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考察了3种不同特点的物料进样方式对乙炔和甲基二氯硅烷的硅氢加成反应的影响;研究了温度、溶剂及乙炔流量等反应条件,对不同进样方式的硅氢加成反应的作用规律.结果表明,物料进样方式不同,反应体系中物料配比及物料混合程度也不同,导致了这一串联硅氢加成反应的硅烷转化率及一次加成选择性极大的差异;在不同进样方式的反应中,反应温度、溶剂等反应条件,表现出极为不同的影响规律;确定了具有高硅烷转化率和一次加成选择性的进样方式以及合适的反应条件.用直接水解的方法制备了聚甲基乙烯基硅氧烷,以此为保护剂,热分解氯铂酸,得到了有高反应活性和稳定性的金属铂胶体. 相似文献
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Pt(DVDS)-Phan催化的末端炔烃的硅氢加成反应 总被引:3,自引:0,他引:3
以Pt(DVDS)-Phan体系作为末端炔烃与三乙基硅烷或三苯基硅烷进行硅氢加成的催化剂, 除三甲基硅乙炔与三乙己硅烷反应外, 其余反应的收率均高于90%, 并且高选择性地或唯一地得到马氏加成产物或者反马氏反式加成产物, 立体选择性或区域选择性超过95%. 相似文献
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聚γ-(m-二苯膦苯基)丙基硅氧烷——铂络合物对烯烃硅氢化反应的催化特征 总被引:3,自引:0,他引:3
本文报道二氧化硅负载的三苯膦铂络合物——聚γ-(m-二苯膦苯基)丙基硅氧烷铂络合物对三甲氧基硅烷与不饱和化合物进行硅氢加成反应的催化特性.在底物用量的万分之一摩尔量的铂络合物存在下,1-己烯、1-癸烯、1-十二碳烯、苯基烯丙醚和ω-氯代十一碳烯在60或40℃平稳地与三甲氧基硅烷发生硅氢加成反应,唯一地得到末端加成产物,产率均在85%以上.其催化活性在反应初期低于四(三苯膦)合铂,但后期反应速度和硅氢化产率均较高.实验表明,聚γ-(m-二苯膦苯基)丙基硅氧烷与四(三苯膦)合铂反应制得的铂络合物(1)比与氯铂酸反应制得的铂络合物(Ⅱ)催化活性高.其次,反应气氛对硅氢加成反应具有决定性的影响.在空气气氛中,硅氢化反应平稳地进行;在氮气气氛中,不发生反应. 相似文献
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C60乙二胺衍生物铂配合物的合成及其催化硅氢化性能 总被引:11,自引:1,他引:10
C60与乙二胺反应,再与氯亚铂酸钾配位,得到了一种以C60衍生物为基的Pt(Ⅱ)配合物,并研究了其在烯烃与三乙氧基硅烷的硅氢加成反应中的催化性能。结果表明,该配合物为硅氢加成反应的高效催化剂,并对苯乙烯有独特的催化性能,以近100%的区域选择性得到α-加成产物。 相似文献
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用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%. 相似文献
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Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction
Laurent Gavara Thomas Boisse Jean-Pierre Hénichart Adam Daïch Philippe Gautret 《Tetrahedron》2010,66(38):7544-5571
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments. 相似文献
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Uroš Grošelj Mojca Žorž Amalija Golobič Branko Stanovnik Jurij Svete 《Tetrahedron》2013,69(52):11092-11108
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives. 相似文献
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The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion. 相似文献
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The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula. 相似文献
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KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields. 相似文献
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Rebecca J. Burton Mandy L. CrowtherNeal J. Fazakerley Shaun M. FilleryBarry M. Hayter Jason G. KettleCaroline A. McMillan Paula PerkinsPeter Robins Peter M. SmithEmma J. Williams Gail L. Wrigley 《Tetrahedron letters》2013
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines. 相似文献
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N. A. Nedolya 《Chemistry of Heterocyclic Compounds》2008,44(10):1165-1219
The review contains a concise historical account and information on the most significant researches undertaken by the staff
at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry
of Heterocyclic Compounds.
Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee.
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008. 相似文献
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N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%). 相似文献
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Shashikant U. Dighe Surya K. Samanta Shivalinga Kolle Sanjay Batra 《Tetrahedron》2017,73(17):2455-2467
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones. 相似文献