Aza-crown ether complex cation ionic liquids: preparation and applications in organic reactions

Yingying Song; Chen Cheng; Huanwang Jing

doi:10.1002/chem.201403118

Aza-crown ether complex cation ionic liquids: preparation and applications in organic reactions

Chemistry. 2014 Sep 26;20(40):12894-900. doi: 10.1002/chem.201403118. Epub 2014 Aug 22.

Authors

Yingying Song¹, Chen Cheng, Huanwang Jing

Affiliation

¹ State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, 222 South Tianshui Rd, Lanzhou (P.R. China), Fax: (+86) 0931-8912582.

PMID: 25154312
DOI: 10.1002/chem.201403118

Abstract

Aza-crown ether complex cation ionic liquids (aCECILs) were devised, fabricated, and characterized by using NMR spectroscopy, MS, thermogravimetric differential thermal analysis (TG-DTA), elemental analysis and physical properties. These new and room-temperature ILs were utilized as catalysts in various organic reactions, such as the cycloaddition reaction of CO2 to epoxides, esterification of acetic acid and alcohols, the condensation reaction of aniline and propylene carbonate, and Friedel-Crafts alkylation of indole with aldehydes were investigated carefully. In these reactions, the ionic liquid exhibited cooperative catalytic activity between the anion and cation. In addition, the aza-[18-C-6HK][HSO4]2 was the best acidic catalyst in the reactions of esterification and Friedel-Crafts alkylation under mild reaction conditions.

Keywords: alkylation; cooperative catalysis; crown compounds; esterification; ionic liquids; synthetic methods.