The effect of TPPTS [p(m-C6H4SO3Na)3], RhCl(CO)(TPPTS)2 and olefin on CMC (critical micelle concentration) of the aqueous solution containing cationic surfactant cetyltrimethylammonium bromide (CTAB) was studied by the maximum bubble pressure method. The apparent molar mass of micelle was determined by a light scattering method. The results showed that the addition of TPPTS and RhCl(CO)(TPPTS)2 into aqueous solutions of CTAB caused the decrease of CMC and the increase of the apparent molar mass of micelle. The data supported the suggestions about enrichment of rhodium catalyst in micelle interface layer and about the solubilization of olefin in micelle. This explanation was confirmed by the measurements of rhodium concentration in the interface layer using ICP method. The acceleration mechanism of long chain olefin hydroformylation in a biphasic catalytic system containing a cationic surfactant was provided.

The hydroformylation of 1-dodecene catalyzed by RhCl (CO) (TPPTS) 2-BISBIS [TPPTS: P (m-C6 H4 SO3 Na) 3, BISBIS: sulfonated 1,1-bis (diphenylphosphino methyl)-2, 2-biphenyl] in aqueous/organic two-phase systemwas studied. The addition of cationic surfactant cetyltrimethylamonium bromide (CTAB) greatly accelerated the reaction rate and the high regioselictivity for linear aldehyde using diphosphine as ligand was attained under two-phase conditions. Both high activity (TOF: 740 h−1) and excellent regioselectivity (96.5% of 1-tridecanal) were obtained at 120℃, 2.0 MPa and [BISBIS]/[Rh] ratio of 3 in thepresence of CTAB.

The enantioselective hydrogenation of ethyl pyruvate in the presence of TS-1 supported rhodium nanoclusters and chiral modifier cinchonidine, cinchonine and quinine was investigated. The results showed that cinchonidine was the best modifier and THF was an excellent solvent for the reaction. Cinchonidine and quinine not only induced the enantioselectivity, but also accelerated the reaction. The interaction between the support and rhodium nanoclusters, as well as the adsorption of modifier on the support surface played an important role in promoting the increase of the catalytic activity and enantioselectivity. Under the optimum conditions, 268 K, 7MPa of hydrogen pressure and 4.0×10−3 mol/l of cinchonidine in THF, the mole conversion of ethyl pyruvate and enantiomeric excess of R-ethyl lactate reached up to 100 and 63.1%, respectively.

研究了奎宁作手性修饰剂修饰的负载型纳米铑簇合物催化剂(Rh PV P2C2A l2O 3)催化丙酮酸乙酯不对称氢化反应， 在该反应中手性修饰剂奎宁不仅具有手性诱导作用，而且还有明显加速反应的作用；载体C2A l2O 3在促进提高催化剂活性和对映选择性方面也有很重要的影响。在优化的反应条件[20 ℃，7.0M PaH2, c (奎宁) = 3.86×10-3mo lL，四氢呋喃作溶剂]下, 丙酮酸乙酯不对称加氢的转化频率(TO F) 为871h-1, 对映选择性达到了54.7%；反应温度降低到3 ℃时, 对映选择性达到59.2%。

The promotional effect of cationic gemini surfactants for the hydroformylation of 1-dodecene in the organic/aqueous biphasic catalytic system is reported. Cationic gemini surfactants with a flexible spacer (G(Eth), G(But) and G(Hex)) and rigid spacer (G(Xyl)) group were used in the reaction. The critical micelle concentration (CMC) and solubilization of laurylbenzene in gemini surfactant solutions were determined. The influence of the concentration of gemini surfactants and the stirring rate on 1-dodecene hydroformylation were investigated. The reaction results showed that in the biphasic catalytic system the hydroformylation of 1-dodecene catalyzed by RhCl(CO)(TPPTS)2-TPPTS [TPPTS = tris(sodium-m-sulfonatophenyl) phosphine] in the presence of gemini surfactants occurred with higher turn over frequency (TOF) and higher regioselectivity toward linear aldehyde (L/B) than those obtained with the conventional monomeric surfactant CTAB. The phenomena could be attributed to the fact that the gemini surfactant has lower CMC and better surface tension reduction ability; moreover it could form more compact and spherocylindrical micelle in the solution. These properties would be favorable for the decrease in the phase transfer energy barrier, thereby greatly accelerating the reaction rate. Meanwhile, the more compact structure of the spherocylindrical micelle formed from gemini surfactant could construct a favorable microenvironment for the formation of linear aldehyde. The comparison of the acceleration effect of the three type surfactants (monomeric surfactant CTAB (cetyltrimethylammonium bromide), gemini surfactant G(Eth), G(But), G(Hex)), G(Xyl) as well as double chain surfactant DCMAB (di(cetylmethyl)ammonium bromide) indicated that the surfactant structure had an important effect on the reaction rate. Their promotion order is DCMAB> G(Eth)≈G(But)≈G(Hex)≈G(Xyl) > CTAB.