Nano-SiO2/DBN: an efficacious and reusable catalyst for one-pot synthesis of tetrahydrobenzo[b]pyran derivatives

Maryam Mehravar,Abdolhamid Bamoniri,Bi Bi Fatemeh Mirjalili,Elaheh Babaei

doi:10.1186/s13065-021-00760-3

Maryam Mehravar, Abdolhamid Bamoniri + Show 2 more

Open Access

https://doi.org/10.1186/s13065-021-00760-3

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Journal: BMC Chemistry	Publication Date: May 21, 2021
Citations: 19	License type: open-access

Affiliation: Yazd University, University of Kashan

Abstract

BackgroundThe nano-sized particles enhance the exposed surface area of the active part of the catalyst, thereby increasing the contact between precursors and catalyst considerably. In this study, nano-SiO2/1,5-diazabicyclo[4.3.0]non-5-en was synthesized, characterized and used as a heterogeneous nanocatalyst for the synthesis of tetrahydrobenzo[b]pyran derivatives. Fourier Transform Infrared Spectroscopy, Field Emission Scanning Electron Microscopy, Brunauer–Emmett–Teller plot, Energy Dispersive X-ray Spectroscopy and Thermo Gravimetric Analysis were used to discern nano-SiO2/1,5-diazabicyclo[4.3.0]non-5-en.ResultsTetrahydrobenzo[b]pyrans were synthesized by using nano-SiO2/1,5-diazabicyclo[4.3.0]non-5-en via one-pot three-component condensation of malononitrile, aldehydes and dimedone in H2O/EtOH at 60 °C. The results indicate that tetrahydrobenzo[b]pyrans were synthesized in good to high yields and short reaction times.ConclusionsThe fundamental privileges of this method are short reaction time, plain procedure, recyclability of catalyst and high yields of products.

Highlights

Multi-component reactions (MCRs) have significant role in organic chemistry, because of some merits like selectivity, synthetic convergence, high atom economy, simplicity, short reaction time, facility of workup, synthetic efficiency and high yield of products [1, 2]
In this research a practical, simple and inexpensive procedure for the synthesis of tetrahydrobenzo[b]pyran derivatives is reported by the reaction of aldehydes, malononitrile and dimedone in the presence of catalytic amount of nano-silica supported 1,5-diazabicyclo[4.3.0] non-5-en (Nano-SiO2/DBN)
A new catalyst was prepared as nano-SiO2/DBN in two steps

Summary

Results

Tetrahydrobenzo[b]pyrans were synthesized by using nano-SiO2/1,5-diazabicyclo[4.3.0]non-5-en via one-pot three-component condensation of malononitrile, aldehydes and dimedone in H 2O/EtOH at 60 °C. The results indicate that tetrahydrobenzo[b]pyrans were synthesized in good to high yields and short reaction times

Introduction

Materials and methods

Results and discussion

Conclusion