2035-08-7Relevant academic research and scientific papers
One-pot synthesis of ordered mesoporous zirconium oxophosphate with high thermostability and acidic properties
Miao, Zhichao,Xu, Leilei,Song, Huanling,Zhao, Huahua,Chou, Lingjun
, p. 1942 - 1954 (2013/07/26)
A series of mesoporous zirconium oxophosphate (M-ZrPO) with different P/Zr molar ratios (0-1.25) has been prepared via a facile one-pot evaporation-induced self-assembly (EISA) strategy. After removing the structure-directing agents, the M-ZrPO with large specific surface area (160 m2 g-1), big pore volume (0.26 cm3 g-1) and narrow pore size distribution (5.64 nm) has been obtained. Small-angle X-ray diffraction (SXRD) and transmission electron microscopy (TEM) results showed that these materials had ordered mesoporous structure. With the increase of P/Zr, the textural properties of M-ZrPO could be improved. Moreover, the ordered mesostructure could be maintained even when treated at 800°C, indicating the M-ZrPO had attractive thermal stability. NH3-TPD and pyridine-IR analyses showed the presence of abundant Broensted and Lewis acid sites in the material. The M-ZrPO has been used successfully as solid acid catalyst and showed excellent performance in the ketalization reaction.
A convenient catalytic method for the synthesis of ethers from alcohols and carbonyl compounds
Fujii, Yasuyuki,Furugaki, Hisakazu,Tamura, Eiko,Yano, Shinji,Kita, Katsumi
, p. 456 - 463 (2007/10/03)
Dialkyl ethers and alkyl fluoroalkyl ethers are obtained in excellent yields by the reaction of alcohols and carbonyl compounds in the presence of Pd/C under the atmospheric pressure of hydrogen, when water produced by the reaction is continuously removed by bubbling hydrogen through the reaction mixture.
Solvent free protection of carbonyl group under microwave irradiation
Perio, Bertrand,Dozias, Marie-Joelle,Jacquault, Patrick,Hamelin, Jack
, p. 7867 - 7870 (2007/10/03)
Protection of aldehydes and ketones as acetals or dioxolanes catalysed by PTSA or KSF clay was readily achieved from orthoformates, 1,2-ethanediol or 2,2-dimethyl-1,3-dioxolane without solvent under microwave irradiation.
Synthesis of 1,3-dioxolanes catalysed by AlPO4 and AlPO4-Al2O3: kinetic and mechanistic studies
Bautista, Felipa M.,Campelo, Juan M.,Garcia, Angel,Leon, Josefa,Luna, Diego,Marinas, Jose M.
, p. 815 - 822 (2007/10/02)
A number of aldehydes and ketones were easily and quantitatively converted to the corresponding 1,3-dioxolanes by the reaction with ethylene glycol over four synthetic amorphous AlPO4 and AlPO4-Al2O3 catalysts using acetonitrile as the solvent at different temperatures in the range 30-60 deg C without the formation of any by-product.The influence of the number of acid sites on the catalyst surface as well as the substituent effects of different carbonyl compounds studied can be evaluated through several isokinetic parameters obtained owing to the existence of a linearfree-energy relationship (LFER).The results obtained account for an intermediate in the transition state whose relative stability is determined by the resonance between the carbonyl group and their substituents, but its evolution is via a concerted process in two adsorption-desorption steps.
