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131.
Marie-Christine DuclosYuttapong Singjunla Christelle PetitAlain Favre-Réguillon Erwann JeanneauFlorence Popowycz Estelle MétayMarc Lemaire 《Tetrahedron letters》2012,53(45):5984-5986
P-Chirogenic monodentate binaphthyl phosphines were prepared in five steps from enantiomerically pure BINOL. This approach supposes the utilization of two methods previously developed in our group, the formation of secondary phosphine oxide, and the reduction of tertiary phosphine oxide using the association of tetramethyldisiloxane and Ti(OiPr)4. During the last reduction step, only the formation of the more stable diastereoisomer was observed. This product was employed as a ligand for the palladium catalyzed hydrosilylation of styrene to afford the corresponding alcohol with high yield and enantiomeric excess. 相似文献
132.
Antonio Antiñolo Rafael Fernández-Galán Antonio Otero Ana M. Rodríguez 《Journal of organometallic chemistry》2009,694(13):1959-3497
The allyl-substituted group 4 metal complexes [M{(R)CH(η5-C5Me4)(η5-C5H4)}Cl2] [M = Ti, R = CH2CHCH2, (2); R = CH2C(CH3)CH2 (3); M = Zr, R = CH2CHCH2 (4), R = CH2C(CH3)CH2 (5)] have been synthesized by the reaction of allyl ansa-magnesocene derivatives and the tetrachloride salts of the corresponding transition metal. The dialkyl complexes ] [M = Ti, R = CH2=CHCH2, R′ = Me (6), R′ = CH2Ph (7); R = CH2C(CH3)CH2, R′ = Me (8), R′ = CH2Ph (9); M = Zr, R = CH2CHCH2, R′ = Me (10), R′ = CH2Ph (11); R = CH2C(CH3)CH2, R′ = Me (12), R′ = CH2Ph (13)] have been synthesized by the reaction of the corresponding ansa-metallocene dichloride complexes 2-5 and two molar equivalents of the alkyl Grignard reagent. Compounds 2-5 reacted with H2 under catalytic conditions (Wilkinson’s catalyst or Pd/C) to give the hydrogenation products [M{(R)CH(η5-C5Me4)(η5-C5H4)}Cl2] [M = Ti and R = CH2CH2CH3 (14) or R = CH2CH(CH3)2 (15); M = Zr and R = CH2CH2CH3 (16) or R = CH2CH(CH3)2 (17)]. The reactivity of 2-5 has also been tested in hydroboration and hydrosilylation reactions. The hydroboration reactions of 3, 4 and 5 with 9-borabicyclo[3.3.1]nonane (9-BBN) yielded the complexes [M{(9-BBN)CH2CH(R)CH2CH(η5-C5Me4)(η5-C5H4)}Cl2] [M = Ti and R = H (18); M = Zr and R = H (19) or R = CH3 (20)]. The reaction with the silane reagents HSiMe2Cl gave the corresponding [M{ClMe2SiCH2CHRCH2CH(η5-C5Me4)(η5-C5H4)}Cl2] [M = Ti and R = H (21); M = Zr and R = H (22) or R = CH3 (23)]. The reaction of 22 with t-BuMe2SiOH produced a new complex [Zr{t-BuMe2SiOSi(Me2)CH2CH2CH2CH(η5-C5Me4)(η5-C5H4)}Cl2] (24) through the formation of Si-O-Si bonds. On the other hand, reactivity studies of some zirconocene complexes were carried out, with the insertion reaction of phenyl isocyanate (PhNCO) into the zirconium-carbon σ-bond of [Zr{(n-Bu)CH(η5-C5Me4)(η5-C5H4)}2Me2] (25) giving [{(n-Bu)CH(η5-C5Me4)(η5-C5H4)]}Zr{Me{κ2-O,N-OC(Me)NPh}] as a mixture of two isomers 26a-b. The reaction of [Zr{(n-Bu)(H)C(η5-C5Me4)(η5-C5H4)}(CH2Ph)2] (27) with CO also provided a mixture of two isomers [{(n-Bu)CH(η5-C5Me4)(η5-C5H4)]}Zr(CH2Ph){κ2-O,C-COCH2Ph}] 28a-b. The molecular structures of 4, 11, 16 and 17 have been determined by single-crystal X-ray diffraction studies. 相似文献
133.
Julien Garcia Daniel J.M. Meyer Denis Guillaneux Michel Wong Chi Man 《Journal of organometallic chemistry》2009,694(15):2427-2433
Titanium-catalysed dehydrocondensation and hydrosilylation of primary, secondary and tertiary phenylsilanes have been investigated in a one-pot process with Cp2Ti(OPh)2 as catalyst by NMR studies. Only primary and secondary silanes were found to undergo simultaneous dehydrogenative coupling and hydrosilylation reactions to produce the functional polysilanes. 相似文献
134.
Andrónico Neira-Carrillo Ranjith Krishna Pai M. Soledad Fernández Esteban Carre?o Patricio Vasquez Quitral Jose Luis Arias 《Colloid and polymer science》2009,287(4):385-393
The objective of this work was to synthesize a sulfonated polymethylsiloxane (S-PMS) by hydrosilylation and sulfonation reactions
and to investigate their effect on the growth of CaCO3 crystals using a gas diffusion method as a function of concentration, pH, and time. The result of IR and NMR shows good agreement
with all proposed structures. Scanning electron microscopy images of CaCO3 showed small well-defined calcite-forming short piles (ca 5 μm) and elongated calcite (ca 20 μm) crystals. The morphology
of the resultant CaCO3 crystals reflects the electrostatic interaction of sulfonate moieties and Ca2+ modulated by S-PMS adsorbed onto the CaCO3 surface. X-ray diffraction confirmed the crystalline calcite polymorph. Energy dispersive spectroscopy of CaCO3 crystals determined the presence of Si atoms from S-PMS. The use of PMS chemistry as an organic additive for the production
of CaCO3 particles is a viable approach for studying the biomineralization and could be useful for the design of novel materials with
desirable shape and properties. 相似文献
135.
In this communication we report a novel, technologically promising procedure able to graft alkynes onto Si(1 0 0) through the formation of direct Si-C bond. It results in the formation of grafted layers as FTIR measurements demonstrates. The advantages of this procedure compared to other available routes are that chemicals used are relatively harmless compared to those used in other wet chemical procedures; and that no surface pre-activation is required, the overall process being surface preserving, i.e. leading to no increase of surface roughness. Furthermore, the reaction mechanism guarantees full stereoselectivity. Therefore, gas sensors built using such a procedure are expected to show higher reliability and more stable electrical behavior. 相似文献
136.
Biphenyl-contained monomer of 1,4-bis[2-(3,4-epoxy cyclohexyl ethyl) dimethylsilyl] biphenyl(BP-Si H-EP) was prepared via hydrosilylation reaction of 1,4-bis(dimethylsilyl) biphenyl(BP-Si H) and 1,2-epoxy-4-vinylcyclohexane in the presence of Karstedt's catalyst. ~1H-NMR, ~(13)C-NMR and FTIR were used to characterize the structure of the obtained monomer. BP-Si H-EP was then cured by methyl hexahydrophthalic anhydride(Me HHPA) with 1-cyanoethyl-2-ethyl-4-methylimidazole as an accelerator. The polymerization behavior was studied by DSC. The results of DMA measurement demonstrate that the cured BP-Si H-EP/Me HHPA can maintain high storage modulus(1 GPa) in a wide range of temperature up to 176 °C. According to the damping factor curve of DMA, cured BP-Si H-EP/Me HHPA exhibits a high glass transition temperature(T_g) of 192 ° C, which is 20 ° C higher than that of cured 1,4-bis[2-(3,4-epoxy cyclohexyl ethyl)dimethylsilyl] benzene(DEDSB)/Me HHPA. TGA results show that cured BP-Si H-EP/Me HHPA has good thermal stability(T_(5% )= 339 ° C) due to the high heat-resistance of rigid biphenyl group. Moreover, the crosslinking density of cured BP-Si H-EP/Me HHPA should be lower than that of cured DEDSB/Me HHPA estimated from their chemical structures, which conflicts with the calculated results based on the rubber elasticity equation. The inconsistence indicates that the calculated crosslinking densities are not comparable, possibly owing to their differences in the rigidity of polymer chains and intermolecular interaction. 相似文献
137.
以不同分子量的端氢硅油(PDMS)和聚乙二醇二烯丙基醚(PEGDE)为原料,通过硅氢加成合成了系列双键封端的含有机硅和聚乙二醇(PEG)链段的多嵌段共聚物(PDMS-b-PEG)m,再用三甲氧基氢硅烷进行端基官能化,生成三甲氧基硅烷封端的多嵌段聚合物,即含PEG前驱物.含PEG前驱物、含氟前驱物(FMS-9922)与有机硅基体树脂通过缩合聚合制备了含PEG的氟硅双亲弹性防污涂层.通过核磁共振氢谱、红外光谱对PEG前驱物的结构进行了表征.吸水率、SEM-EDS和接触角测试考察了含PEG前驱物中疏水链段的长度,含氟前驱物的含量对涂层表面重排的影响,结果表明PEG前驱物中疏水链段越长,涂层的吸水率越低,在水中越稳定,且表面不易发生重排.而含氟前驱物的加入能促使PEG链段向表面方向迁移.抗蛋白、抗菌和抗藻附着性能测试表明:含有FMS-9922的样品防污性能均优于不含FMS-9922的样品,而且随着FMS-9922用量增加,涂层防污性能呈上升趋势;但是FMS-9922用量太高时,体系相容性下降,防污性能也随之变差,故FMS-9922的含量控制在7%为宜. 相似文献
138.
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:10,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
139.
140.
The commercially available rhodium(I) complex [RhCl(CO)2]2 (1) was shown to be an effective catalyst for the reduction of carbonyls with organosilanes under mild conditions. This study focusses on the hydrosilylation of aldehydes with diphenylsilane leading to the isolation of a series of dialkoxydiphenylsilanes with low catalytic loading of complex 1. 相似文献