Preparation and application of highly efficient and reusable TBAPIL@Si(CH2)3@nano-silica-based nano-catalyst for preparation of benzoxanthene derivatives

Abstract

Tetrabutylammonium prolinate ionic liquid (TBAPIL) was prepared, and mesoporous silica nanoparticles (NPs) were synthesized. Both of these were linked through propyltriethoxysilane to prepare a reusable catalyst TBAPIL@Si(CH2)3@silica NPs (TBAPILS). The formation of TBAPIL was checked through Fourier-transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance (NMR) analysis. X-ray diffraction analysis confirmed the structure of silica NPs and linking of TBPAIL on it. Transmission electron microscopy proved the flourishing development of silica NPs. Scanning electron microscopy graphs exposed the altering in morphology of silica NPs and TBAPILS. FT-IR analysis also confirmed the formation of TBAPILS catalyst. Moreover, the effectiveness of the TBAPILS was also checked for the synthesis of various derivatives of tetrahydrobenzoxanthenes-11-ones. The formation and structure of obtained compounds were confirmed by FT-IR, elemental analysis, 1HNMR and 13C NMR spectral analysis. The catalyst TBAPILS was found to be used successfully up to five cycles without significant loss of activity.