Enantioselective hydrogenation of acetophenone by(1S,2S)-DPEN-Ru(Ⅱ)Cl_2(PPh_3)_2 encapsulated in Al-MCM-41

A chiral ruthenium complex[（1S,2S）-DPEN]-RuCl_2（PPh_3）_2（DPEN = 1,2-diphenylethylenediamine,PPh_3 = triphenylphosphine） was encapsulated in the channel of Al-MCM-41 by electrostatic adsorption and 1,1-dichlorosilacyclobutane modification.The prepared heterogeneous catalyst showed the same catalytic activity and enantioselectivity as the corresponding homogeneous catalyst in the asymmetric hydrogenation of acetophenone,and could be reused at least seven times without significant loss of catalytic activity and enantioselectivity.

EFFECT OF ELECTRON DONORS ON THE SELECTIVE HYDROGENATION OF DIENE TO MONOENE OVER HETEROGENIZED Pd CATALYST

In the selective hydrogenation of diene (or alkyne) using heterogenized homogeneous catalyst, the high selectivity of monoene formation only appears in a very short time interval. The addition of suitable electron donors can decrease or even cease the monoene hydrogenation and thereby keep the high monoene selectivity after reaching its maximum.

Heterogeneous uptake of gaseous hydrogen peroxide on mineral dust

The heterogeneous uptake processes of hydrogen peroxide on Arizona test dust and two types of authentic Chinese mineral dusts, i.e., Inner Mongolia desert dust and Xinjiang calciferous dust, were investigated using a Knudsen cell reactor coupled with a quadrupole mass spectrometer. The uptake coefficients were measured as a function of the initial concentration of H_2O_2 from 2.6 × 10^（11） to 1.2 × 10^（12）molecules/cm^3, and the temperature dependence of the uptake coefficients was investigated over a range from 253 to 313 K. The concentration of H_2O_2 showed little effect on the uptake coefficients of these heterogeneous processes. As a function of temperature, the initial uptake coefficients decrease with increasing temperature, whereas the steady state uptake coefficients of Arizona test dust and Inner Mongolia desert dust increase with increasing temperature. Implications for the understanding of the uptake processes onto mineral dust samples were also discussed.

Immobilization of chiral Rh catalyst on glass and application to asymmetric transfer hydrogenation of aryl ketones in aqueous media

A chiral catalyst, Cp＊RhTsDPEN （Cp＊ = pentamethyl cyclopentadiene, TsDPEN = substitutive phenylsulfonyl-l,2-diphenylethylenediamine）, was synthesized and immobilized at the surface of glass. The immobilized catalyst exhibited good catalytic efficiency for asymmetric transfer hydrogenation of aromatic ketones in water with HCOONa as hydrogen source.

Selective hydrogenation of unprotected indole to indoline over N-doped carbon supported palladium catalyst

Mesoporous N-doped carbon supported palladium catalyst Pd@CN0.132 was able to efficiently catalyze unprotected indole to indoline under mild conditions.In the aqueous system,a selectivity of 100% and conversion of 96% was achieved under 313 K and atmospheric hydrogen gas.

Selective oxidation of alcohols with H2O2 catalyzed by zinc polyoxometalate immobilized on multi-wall carbon nanotubes modified with ionic liquid

In this work,acid functionalized multi-wall carbon nanotubes（MWCNTs） were modified with imidazolium-based ionic liquids.The selective oxidation of various alcohols with hydrogen peroxide catalyzed by [PZnMo2W9O39]^5-,ZnPOM,supported on ionic liquids-modified with MWCNTs,MWCNTAPIB,is reported.This catalyst[ZnPOM@APIB-MWCNT],was characterized by X-ray diffraction,scanning electron microscopy（SEM） and FT-IR spectroscopic methods.This heterogeneous catalyst exhibited high stability and reusability in the oxidation reaction without loss of its catalytic performance.