Esterifications of alcohols with carboxylic acids in the room temperature ionic liquid 1-butylpyridinium chloride–aluminium(III) chloride as green reaction medium in catalytic quantities have been investigated. Excellent conversion and selectivities were achieved, and the most of resultant esters could be easily recovered due to immiscibility with the ionic liquid.

★★★☆☆ Keywords: Ionic liquid; Esterification; Catalyst

★★★☆☆ Y. Deng et al. / Journal of Molecular Catalysis A: Chemical 165 (2001) 33–36.

Under mild conditions and without any additional organic solvents, Beckmann rearrangements of several ketoximes were performed in the catalytic media consisting of room temperature ionic liquid based on 1,3-dialkylimidazolium or alkylpyridinium salts and phosphorated compounds. Excellent conversion and selectivity was achieved for cyclohexanone oxime as the substrate, while Beckmann fragmentation of cyclopentanone oxime was observed.

★★★★☆ J. Peng, Y. Deng : Tetrahedron Letters 42 (2001) 403–405.

The syntheses of disubstituted ureas by carbonylation of a series of amines in the presence of a sulfate modified zirconia supported palladium catalyst was investigated at an initial total pressure of 4.0 MPa and 135°C. High conversions and yields were achieved for the synthesis of symmetric dialkylureas. This supported catalyst could also be easily separated and recovered after reaction.

★★★★☆ F. Shi et al. : Tetrahedron Letters 42 (2001) 2161–2163.

In room temperature ionic liquids based on 1-n-butyl-3-methylimidazolium and n-butylpyridinium salts, cycloaddition of carbon dioxide to propylene oxide without any additional organic solvents has been investigated. It was found that 1-n-butyl-3-methylimidazolium tetraÑuoroborate was the most active catalyst with almost 100% selectivity, and a suitable CO oxide molar ratio was needed for high conversion. The ionic liquid used 2Èpropylene as catalyst for the reaction was recyclable.

★★★☆☆ Jiajian Peng and Youquan Deng. New J. Chem., 2001, 25, 639È641

The catalytic activity of Au/Co3O4 (Au loading was 2–5 wt.%) towards methane combustion could be enhanced when small amount of Pt, e.g. 0.2 wt.% was added, and the temperature for 100% conversion of methane could be decreased by 50◦C. Palladium, which was the most active single metal catalyst for methane combustion, on the other hand, exhibited lower catalytic activity than Au–Pt/Co3O4 when combined with Au over the Co3O4 support.

★★★☆☆ Keywords: Methane; Catalytic combustion; Au–Pt/Co3O4

★★★☆☆ S. Miao, Y. Deng / Applied Catalysis B: Environmental 31 (2001) L1–L4.

Alkylations of benzene with dodecene and/or chloromethanes in the chloroaluminate room temperature ionic liquid modified with HCl as catalysts have been investigated. Different product distributions and enhanced activity, were respectively observed for these two alkylation reactions. This may be attributed to the superacidity of the ionic liquid induced by the presence of HCl.

★★★☆☆ Keywords: Ionic liquids; Alkylation; Benzene; Superacidity

★★★☆☆ K. Qiao, Y. Deng. Journal of Molecular Catalysis A: Chemical 171 (2001) 81–84.

3,4-Dihydropyrimidin-2(1H)-ones were synthesised in high yields by one-pot three-component Biginelli condensation in the presence of room temperature ionic liquids such as 1-n-butyl-3-methylimidazolium tetrafluoroborate (BMImBF4) or hexafluorophosphorate (BMImPF6) as catalysts under solvent-free and neutral conditions.

★★★★☆ Jiajian Peng and Youquan Deng. Tetrahedron Letters 42 (2001) 5917–5919.

At 170 degreesC and ca. 4.0 MPa, oxidative carbonylation of aromatic amines to synthesize corresponding carbamates over a novel PdCl2/ZrO2-SO42- catalyst could proceed with high conversion and selectivity.

★★★☆☆ Feng Shi, Youquan Deng,1 Tianlong SiMa, and Hongzhou Yang. Journal of Catalysis 203, 525–528 (2001).

A novel synthesis of several dialkylureas by electrocatalytical carbonylation of aliphatic amines was investigated at 30 degreesC and atmospheric pressure in the presence of Pd(II) and Cu(II) cocatalyst., This catalyst system was very effective for the carbonylation of primary mono-amines. Furthermore, the phenomenon of the non-Faradic electrochemical modification of catalytic activity was observed in this homogeneous reaction system and the current efficiency for dialkylurea formation reached 401%.

★★★☆☆ Keywords: Carbon monoxide; Electrocatalysis; Aliphatic amines; Carbonylation; Dialkylurea

★★★☆☆ H. Yang et al. / Journal of Molecular Catalysis A: Chemical 176 (2001) 73–78.

At 200 degreesC and 5 MPa of initial total pressure, the oxidative carbonylation of amines for the synthesis of the corresponding carbamates by Au(i) complexes as catalysts was conducted with excellent conversion and selectivity.

★★★★☆ Shi, F; Deng, YQ. Chem. Commun., 2001, 443–444.