A series of highly efficient polymer-immobilized gold catalysts were prepared for the oxidative carbonylation of aniline and its derivatives to obtain carbamates and symmetric ureas in a clean, simple, solvent-free, and obtainable product-ready way.TEM showed that the average gold particle size of fresh catalyst was less than 10 nm.

★★★☆☆ Feng Shi and Youquan Deng. Journal of Catalysis 211, 548–551 (2002).

At 170°C and using ionic liquids as solvent and catalyst, primary and secondary aliphatic amines could react with dimethyl carbonate to give alkyl carbamates with good yield. Due to its insolubility, the desired carbamate solid could be recovered by simple filtration from the two-layer mixture of dimethyl carbonate and ionic liquid after reaction and the formation of N-methylated and deammoniated products were restrained.

★★★★☆ T. Sima et al. / Tetrahedron Letters 43 (2002) 8145–8147.

Hydroesterification of tert-butyl alcohol with ethanol catalyzed by transition metal triphenylphosphine complexes in the presence of p-toluenesulfonic acid was investigated using room temperature ionic liquids as the reaction medium at 373–413 K and 3–6 MPa of CO. In comparison with the organic solvents as reaction medium, higher conversion was achieved and ethyl tert-valerate could be directly formed in the ionic liquid medium. The products could be separated from the ionic liquids easily due to their immiscibility in this medium.

★★★☆☆ Kun Qiao and Youquan Deng. New J. Chem., 2002, 26, 667–670.

Electrocatalytic cycloaddition of carbon dioxide to epoxides in room temperature ionic liquids as reaction media without any additional supporting electrolyte and catalyst could be conducted with high to excellent performances under mild conditions.

★★★★☆ Hongzhou Yang, Yanlong Gu, Youquan Deng and Feng Shi. CHEM. COMMUN., 2002, 274–275.

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.