▎ 摘　　要

Ionic liquids have been established as solvents and catalysts in a number of reactions due to their unique properties. In this study, we have synthesized sulfonic acid functionalized imidazolium based strongly acidic ionic liquid supported on graphene oxide (PTS-Im-3@GO). PTS-Im-3@GO was synthesized by grafting 1-(4-sulfobutyl)-3-(3-propyltriethoxysilyl)imidazolium hydrogen sulfate onto graphene oxide (GO) by covalent bonds. The prepared PTS-Im-3@GO was used for regio-selective ring opening reaction of styrene oxide with isopropyl alcohol giving 95% conversion and 100% regio-selectivity towards 2-isopropoxy-2-phenylethan-1-ol at 50 degrees C. The activity of the said catalyst was compared with various heterogeneous catalysts such as GO, PTS-Im-1@GO, PTS-Im-2@GO, PTS-Im-1, PTS-Im-2, PTS-Im-3, H beta-zeolite, and montmorillonite K-10. Among all catalysts, PTS-Im-3@GO showed good conversion towards the desired product. PTS-Im-3@GO was characterized by FTIR, SEM, EDS, TGA, XRD, Si-29 NMR, XPS and CHNS analysis. Systematic studies demonstrated that PTS-Im-3@GO had excellent catalytic activity and regio-selectivity for the alcoholysis of epoxides rendering beta-alkoxy alcohols and aminolysis of epoxide giving beta-amino alcohols in very good yields. The protocol is clean and green.