Mesoporous ZnO/AlSBA-15 (7) Nanocomposite as An Efficient Catalyst for Synthesis of 3,4-dihydropyrimidin-2(1H)-one via Biginelli Reaction and Their Biological Activity Study

Abstract

In this study, the mesoporous ZnO/AlSBA-15 (Si/Al=7) nanocomposite catalyst was prepared by using a combination of direct and impregnation procedure. The catalyst was characterized by X-ray diffraction (XRD), scanning electron microscope coupled with energy-dispersive x-ray spectroscopy (SEM-EDS), N2 adsorption-desorption isotherm, Fourier transform infrared spectroscopy (FT-IR), and Temperature programmed reduction (TPR-H2). The XRD and N2 sorption results show the hexagonal mesoporous nature of catalyst with type IV adsorption isotherm. The surface area was calculated by the BET method and found to be 373 m2/g. From the TPR-H2 study, the reducibility temperature of ZnO found to be 966 K. Further, the Biginelli reaction is a promising multi-component reaction in organic synthetic chemistry as it approaches the green chemistry protocols and adducts are extensively used as drugs, intermediate and in medicine. Hence, the catalytic activity was tested in one pot Biginelii reaction for the synthesis of 3,4-dihydropyrimidin-2(1H)-one's derivative. The product yield was observed to be 96% at temperature 333 K, at the short response time of 4 h. The two adducts were examined by 1HNMR, 13CNMR, and FT-IR spectroscopy. Besides, the biological activity of adduct (A) C15H18N2O5 was explored by gram-positive bacteria (Staphylococcus aureus) and gram-negative microorganisms (E. coli). The adduct (A) C15H18N2O5 shows a clear inhibition zone of 24 mm against E. Coli whereas Azithromycin shows an inhibition zone of 28 mm. Copyright © 2019 BCREC Group. All rights reserved

Recent developments in metal-doped SBA-15 catalysts for heterogeneous catalysis and sustainable chemistry

“…The only drawback of this method is the lower textural properties of metal-doped SBA-15 compare to the direct synthesis method, as can be seen in Table -1. Notably, wet impregnation methods do not alter the geometrical structure (2D hexagonal) and remain similar to bare SBA-15 [11,47] . (R-CHO) as depicted in scheme-1 [9] .…”

“…Bhuyan et al reported the ZnO/SBA-15 catalyst for this transformation reaction. However, Mahato, BN et.al reported the ZnO/Al-SBA-15 catalyst as superior, efficient with 98 % yield at a lower temperature, and a short time making the reaction greener [11] .…”

Efficient one-pot synthesis of 4-hydroxy-2H chromene by heterogeneously catalyzed ZnO NP and mesoporous aluminosilicate catalysts in solvent free condition

“…The catalyst ZnO/AlSBA-15 (7) was prepared by hydrothermal method and characterized XRD, SEM, BET surface area, FTIR, TPR-H 2 in our previous studies [18] . We used the material in this study for comparison purposes in catalytic studies.…”

“…Moreover, SBA-15 is an outstanding and excellent 2D mesoporous material widely used in adsorption, catalysis, and preparation of fine chemicals owing to high surface area (1000 m 2 /g), tunable pore size (3-30nm), thick wall, greater hydrothermal stability (up to 800 deg. C), and greater accessibility [15][16][17][18][19] . The acidity of SBA-15 can be enhanced by incorporating various functional groups or metal atoms during the synthesis or by the post-grafting method.…”

Recent Advances in Homogeneous and Heterogeneous Catalyst in Biginelli Reaction from 2015‐19: A Concise Review

“…The ZnO@SBA‐15 (Si/Al=7) was reported by Mahato and Krithiga . The average crystalline size is evaluated to be 24 nm.…”