The title compound H2SiW12O40·(CH3)2NH was synthesized in mixed solvent of aqueous and acetonitrile, and its crystal structure had been determined using single crystal X ray diffraction. The crystal belongs to mo...The title compound H2SiW12O40·(CH3)2NH was synthesized in mixed solvent of aqueous and acetonitrile, and its crystal structure had been determined using single crystal X ray diffraction. The crystal belongs to monoclinic, space group C2/m, a=2.0654(4)nm, b=1.3306(3)nm, c=1.3194(3)nm, β=119.59(3)°, V=3.1531(11)nm3, Dc=3.606Mg·m-3, Z=2, R=0.0462, Rw=0.0836. The title compound comprises of a 2+ unit, a polyanion and a free (CH3)2NH molecule. The ESR spectrum of the title compound shows that charge transfer between organic groups and polyanion takes place under irradiation of the sunlight in solid state. The TG study of the title compound shows that it had four stages of the weight loss, and the increase of the decomposition temperature for the polyanion shows that the stability of the polyanion was enhanced due to the influence of Zn2+ ion. CCDC:175866.展开更多
A nanosolid heteropoly acid of H 3PW 12 O 40 /SiO 2 was prepared with the sol-gel method and used to catalyze sythesis of methyl 5-amino-1,2,4,-trazolylformate sulfate.The structure of the nanosolid heteropoly acid H ...A nanosolid heteropoly acid of H 3PW 12 O 40 /SiO 2 was prepared with the sol-gel method and used to catalyze sythesis of methyl 5-amino-1,2,4,-trazolylformate sulfate.The structure of the nanosolid heteropoly acid H 3PW 12 O 40 /SiO 2 was characterized by IR,XRD and TEM.The following optimum condition were that the mole ratio of alcohol to carboxylic acid is 27∶1,the temperature is 75℃,the reaction time is 5 hours,and the catalyst is 2 5% of feedstock.Under the optimum conditions,the yield of esters was above 94%.展开更多
文摘The title compound H2SiW12O40·(CH3)2NH was synthesized in mixed solvent of aqueous and acetonitrile, and its crystal structure had been determined using single crystal X ray diffraction. The crystal belongs to monoclinic, space group C2/m, a=2.0654(4)nm, b=1.3306(3)nm, c=1.3194(3)nm, β=119.59(3)°, V=3.1531(11)nm3, Dc=3.606Mg·m-3, Z=2, R=0.0462, Rw=0.0836. The title compound comprises of a 2+ unit, a polyanion and a free (CH3)2NH molecule. The ESR spectrum of the title compound shows that charge transfer between organic groups and polyanion takes place under irradiation of the sunlight in solid state. The TG study of the title compound shows that it had four stages of the weight loss, and the increase of the decomposition temperature for the polyanion shows that the stability of the polyanion was enhanced due to the influence of Zn2+ ion. CCDC:175866.
文摘A nanosolid heteropoly acid of H 3PW 12 O 40 /SiO 2 was prepared with the sol-gel method and used to catalyze sythesis of methyl 5-amino-1,2,4,-trazolylformate sulfate.The structure of the nanosolid heteropoly acid H 3PW 12 O 40 /SiO 2 was characterized by IR,XRD and TEM.The following optimum condition were that the mole ratio of alcohol to carboxylic acid is 27∶1,the temperature is 75℃,the reaction time is 5 hours,and the catalyst is 2 5% of feedstock.Under the optimum conditions,the yield of esters was above 94%.
