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.