A highly efficient and regioselective allylation reaction of amines and active methylene compounds directly using allylic alcohols under mild conditions catalyzed by the novel cubane-type sulfido [(Cp*Mo)(3)(mu(3)center dot S)(4)Pd(eta(3)-allyl)][PF6](2) clusters has been developed. A variety of allylic alcohols and nucleophiles including amines and active methylene compounds are investigated, and in the case of allylic alcohols bearing substituents at either the alpha- or gamma-position only linear products are obtained.

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Catalytic properties of HZSM-5s with three different Na+ ion-exchange levels and SiO2 /Al2O3 ratios used in tert-butylation of DHB (1,2-dihydroxybenzene) are interpreted through pyridine adsorbed FT-IR and XPS study. The DHB conversion decreases as increment of degree of Na+ ion-exchange level and of Si content in HZSM-5. Catalytic properties with respect to Na amount in ZSM-5 are more sensitive than those of HZSM-5s with different SiO2/Al2O3 ratios. But selectivity for 4-TBC (4-t-butylcatechol) is not changed significantly. Acidic properties, i.e. acid strength and acid density are characterized by pyridine adsorbed FT-IR and XPS study. Based on FTIR and XPS analyses, DHB conversion and selectivities for DTBC (3,5-di-t-butylcatechol) and 3-TBC (3-t-butylcatechol) depend on type and strength of acid sites, with the result that strong Brønsted acid rather than weak Brønsted or Lewis acid sites are more closely related to the conversion. Furthermore, t-butyl alcohol is selectively adsorbed on the Brønsted acid site of FT-IR band at 3612 cm-1, which signifies that the Brønsted acid site is the active site. The mechanism for t-butylation of DHB is suggested based on the FT-IR results of adsorption/desorption of reactants.

FeCl2 and 3-aminopropyltrimethoxysilane (ATMS) were grafted on Si-MCM-41. FeCl2, FeCl3, FePc(II) and FePc(III)Cl were also grafted with ATMS coupled Si-MCM-41, whose catalytic activities were evaluated by performing hydroxylation of phenol with H2O2. These chemically modified Fe-containing samples were characterized by FT-IR. When the FeCl2/Si-MCM-41 is used, the phenol conversion reveals about 16.5%. ATMS coupled Fe-containing Si-MCM-41 catalysts improve phenol conversion by 1.5–2 times and decrease the formation of benzoquinone remarkably, while catechol/hydroquinone is in the range of 2–3.5. The redox behavior between Fe(II) and Fe(III) is discussed based on ESR spectroscopy.

The alkylation of phenol with propylene has been studied over several H-ZSM-5s with different Si/Al ratios and Cs+-ion-exchanged H-ZSM-5s at temperature range 373–623°C. Both O- and C-alkylation, which were closely dependent on the reaction temperature and acidity of the catalysts, were observed. O-alkylated compound is found to be formed preferably at temperature lower than 250°C and over Cs+-ion-exchanged H-ZSM-5s. However, at higher temperature, only C-alkylation is observed. The acidic properties of the zeolites were characterized by solid-state 31P MAS-NMR of the probe molecule trimethylphosphine oxide and NH3-TPD (temperature-programmed desorption) and it is suggested that in the case of C-alkylation, moderate acid sites are responsible for the formation of para-isopropylphenol, while ortho-isopropylphenol is favorable for weak acid sites.

Isopropylation of phenol with 2-propanol has been carried out over Na-exchanged ZSM-5 zeolites to determine the effect of catalyst acidity on phenol conversion and product selectivity. The acid type and strength of the catalyst such as Lewis, weak and strong Bronsted acid sites are measured by pyridine adsorbed XPS and the catalytic properties are interpreted in terms of the acid properties. The active site and mechanism for the reaction are suggested based on evidence of study from the reactant adsorbed FT-IR.

The alkylation of benzene with 1-dodecene was studied over solid-acid zeolites, such as H-mordenite, H-USY, HY, and H-ZSM-5, in a batch reactor at 140°C and 10 atm. H-mordenite showed the highest selectivity of 78.2% for 2-phenyldodecane with 100% conversion. Depending on the catalyst amount (from 0.5 to 1.0 g) and the molar ratio of benzene to 1-dodecene (from 7 to 10), the conversion of 1-dodecene varied in the range from 63.8 to 100%. Furthermore, modification of H-mordenite by dealumination using nitric acid and by solid ion exchange with Mg2+ and Fe3+ ions led to the improvement of the selectivity for 2-phenyldodecane, and simultaneously reduction of the conversion of 1-dodecene is observed. In addition, it was found by pyridine adsorption FT-IR study that both strong Brønsted and Lewis acid sites are closely related to the conversion.

The butyl group transfer reactions of t-butyl catechols were investigated over the zeolite HBEA and super acid SO4/ZrO2. Melting a physical mixture of 3,5-di-tert-butylcatechol (DTBC), catechol and/or -2-tert-butylcatechol (4-TBC) produced a significant conversion, resulting from the thermal reaction. HBEA exhibits a good conversion and selectivity on 4-TBC through the transalkylation of DTBC and catechol. The super acid sulfated zirconia, SO4/ZrO2, due to its strong acidity, favors the dealkylation and disproportionation of 4-TBC or/and DTBC, preventing the increase of the selectivity on 4-TBC.

The influence of synthesis method on the synthesis of Ti-SiZSM-5 zeolite and the mechanism of synthesis are studied. The synthesis process of Ti-SiZSM-5 zeolite using much cheaper raw materials such as silica sol, [Ti(H2O2)2+], TEAOH and HDA depends strongly on n(SiO2)/n(TiO2), n(Na2O)/n(SiO2) and n(TEAOH+HDA)/n(SiO2). It has been found that Ti-SiZSM-5 can only be obtained at high n(SiO2)/n(TiO2), low n(Na2O)/n(SiO2) in the synthesis hydrogel and the chemical composition of the synthesis hydrogel may be changed in a small range. Seed, structure-directing agent and the hydrogel ripening during the synthesis of Ti-SiZSM-5 zeolite are beneficial to the improvement of crystallinity and the incorporation of Ti into the framework of Ti-SiZSM-5.

在廉价原料水热合成体系中,研究了硅源(工业硅溶胶)、模板剂(无机钛源和廉价有机胺)及杂质对Ti-SiZSM-5分子筛合成的影响.结果表明,硅溶胶聚合度低、胶粒小、Na+含量低时,合成的Ti-SiZSM-5分子筛结晶度高、晶粒均匀,有利于Ti进入分子筛骨架;用无机钛TiO(H2O2)2+溶液和用Ti(OC4H9)4有机钛源一样,可合成出高结晶度的Ti-SiZSM-5分子筛,Ti易进入分子筛骨架;在合成凝胶中加入NaCl可加快晶化速度,合成的分子筛粒度变小,但NaCl阻碍Ti进入分子筛骨架,导致锐钛矿和α-SiO2的生成;合成中带入微量Al3+可提高结晶度和晶化速度,在本实验合成范围内(n(SiO2)/n(Al2O3)>100),没有发现Al3+影响钛进入分子筛骨架,但使合成的分子筛具有明显的酸性,易造成H2O2分解和引起酸催化的副反应;不同廉价模板剂影响合成分子筛的晶貌和晶粒大小,NBA和HDA既可合成出Ti-SiZSM-48,又可合成出Ti-SiZSM-5,合成后者的相区很窄.而混胺(HDA+TEAOH)模板剂有利于Ti-SiZSM-5分子筛的合成,合成相区较单胺为宽、重复性好.