Reactions of propargylic alcohols with CO2 in a [BMIm][PhSO3]/CuCl catalytic system to produce the corresponding R-methylene cyclic carbonates were conducted with high yields. Mild reaction conditions, enhanced rates, improved yields, and recyclable ionic liquid catalyst systems are the remarkable features exhibited in this process. Furthermore, the use of large amounts of tertiary amines as well as nitrogen-containing organic solvent as employed in previously studies was avoided.

★★★★☆ Yanlong Gu, Feng Shi, and Youquan Deng. J. Org. Chem. 2004, 69, 391-394.

The solubilities of taurine (2-aminoethanesulfonic acid (H2NCH2CH2SO3H)) and sodium sulfate in a series of room temperature ionic liquids were examined, and a novel and greener separation method combined with chlorinated dialkylimidazolium ionic liquid as leaching reagent and organic solvent as precipitating reagent was developed. Using such process, selective separation of taurine from solid mixture containing large amount of sodium sulfate could be realized with 67–98.5% of single separation yield. The recycling of ionic liquid and organic solvent used in this separation process is possible.

★★★☆☆ Keywords: Ionic liquid; Leaching separation; Taurine; Solubility; Sodium sulfate

★★★☆☆ Y. Gu et al. / Separation and Purification Technology 35 (2004) 153–159.

Under mild conditions and without any additional organic solvents, Beckmann rearrangement of ketoximes was performed in a novel task-specific ionic liquid consisting sulfonyl chloride. Especially for the conversion of cyclohexanone oxime to e-caprolactam, e-caprolactam has good solubility in water while the task-specific ionic liquid is immiscible with water, therefore, e-caprolactam could be easily separated from the reaction system by water extraction.

★★★★☆ J. Gui et al. / Tetrahedron Letters 45 (2004) 2681–2683.

Addition reactions of aliphatic acids with olefins to give corresponding esters have been investigated using SO3H-functionalized ionic liquids as dual catalyst–solvent. The isolation of the desired products could be achieved via simple decantation and ionic liquids could be reused continuously after dried in vacuum (5–12 mmHg) at ca. 80 ◦C.

★★★☆☆ Y. Gu et al. / Journal of Molecular Catalysis A: Chemical 212 (2004) 71–75.

Several acid functional ionic liquids, in which cations possess two adjacent acid sites, were synthesized and used for the acetalization of aldehydes with good catalytic performance under mild reaction conditions.

★★★★☆ Dongmei Li, Feng Shi, Jiajian Peng, Shu Guo, and Youquan Deng. J. Org. Chem. 2004, 69, 3582-3585.

Cracking of FCC naphtha has been investigated on the model catalysts containing ZSM-5 (Si/Al2 = 50, 500), Zn-ZSM-5 (Si/Al2 = 50) and USY. The presence of ZSM-5 and USY causes a tremendous decrease in olefins of gasoline fraction, leading to an enrichment of the aromatics in liquid product. It is evidently that aromatics are generated from lower olefins. The property of lower silica-to-alumina ratio of ZSM-5 and Zn modification enhance the aromatization process for higher cracking reactivity and dehydrogenation. The result of evaluation in confined fluid bed apparatus (CFBA) with the mixture of VGO and VTB as feed further confirms the aromatics generation in cracking reaction stimulated by ZSM-5 additive over base catalysts with different hydrogen transfer activity. Based on these results, relations between scission and aromatization in FCC catalyst containing ZSM-5 zeolite could be proposed. The suggested reaction path could better explain the reasons that effectiveness of ZSM-5 additive to lighter olefins is more profound in base catalyst of low hydrogen transfer activity and why so many researchers had not observed the aromatics generation motivated by ZSM-5 additive in catalytic cracking reaction.

★★★☆☆ Keywords: ZSM-5; Aromatics generation; Hydrogen transfer activity; Lighter olefins; FCC catalyst

★★★☆☆ C. Liu et al. / Journal of Molecular Catalysis A: Chemical 215 (2004) 195–199.

After modifications of rare earth and phosphorus, the acidity density and the strength in the pores of zeolite Y (PREUSY) are improved effectively; the surface acidity is suitably reduced and weakened owing to the interaction of rare earth cation and phosphate anion. NH3-TPD analysis showed that the acid distribution of the modified zeolite is more concentrated on the range of intermediate and strong acidity. This kind of modification can direct more hydrocarbons to enter into the pores to be converted and remarkably reduces the possibility of naphtha olefins forming through a surface cracking reaction. In addition, because naphtha olefin reduction does not completely depend on olefin saturation through secondary hydrogen transfer reaction, this kind of reaction mode can decrease the excessive cracking of mediate distillate and can improve the diesel oil yield (LCO) effectively. Some reaction pathways were proposed.

★★★☆☆ Keywords: Zeolite Y; Rare earth; Phosphorus; Catalytic cracking reaction; Surface modification; Reducing olefin formation; Diesel oil yield; Hydrogen transfer activity

★★★☆☆ C. Liu et al. / Applied Catalysis A: General 264 (2004) 225–228.

At ambient reaction temperature, the silica gel confined ionic liquid catalysts were perfectly combined with water as an effective catalytic system for simultaneous C@N and C@O bonds transformation with a TONs exceeding 300molmol
-1.

★★★★☆ D. Li et al. / Tetrahedron Letters 45 (2004) 6791–6794.

A brief review of the work carried out at Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences for development of ionic liquid as green reaction media and catalysts is presented. This includes the processes of ionic liquid to be used as catalyst, reaction media, development of functional ionic liquid and methods for synthesis of immobilized ionic liquid. In the end, some prospects for development of ionic liquid are also addressed.

★★★☆☆ KEY WORDS: catalysis; green chemistry; ionic liquid; reaction media; review.

★★★☆☆ F. Shi et al./ Catalysis Surveys from Asia, 2004, 8(3): 179-186.

A novel reaction of cyclization of 1-dodecene to cyclododecane with high selectivity, especially under moderate pressure, is found in ethanol buffered chloroaluminate ionic liquids with easy separation of product duo to the immiscibility with ionic liquids.

★★★★☆ K. Qiao, Y. Deng / Tetrahedron Letters 44 (2003) 2191–2193.