Glycerol and Q-Tubes: Green Catalyst and Technique for Synthesis of Polyfunctionally Substituted Heteroaromatics and Anilines.

Douaa Salman Almarzouq,Noha M Hilmy Elnagdi

doi:10.3390/molecules24091806

Abstract

The role of glycerol as a green bio-based solvent, reactant, and/or a catalyst in the synthesis of novel heterocycles, under pressure, is studied. Synthesis of novel quinolines in good yields using a new modified Skraup synthesis, utilizing glycerol and pressure Q-tubes, is demonstrated. Novel aniline trimers are prepared using glycerol, and substituted anilines under pressure, in acidic medium and water. Glycerol was employed as a catalyst and a green solvent in the synthesis of novel pyridazines 13a–c. The mechanisms of the reactions and the catalytic effect of glycerol in protic and aprotic media are fully discussed. The structures of the synthesized compounds were determined via X-ray crystallography and spectroscopic methods.

Highlights

Glycerol was first isolated by the Swedish chemist: Carl W
We initially started our work with the synthesis of quinolines
We thought of investigating this phenomenon as well as modifying the Skraup quinoline synthesis using pressure Q-tubes, and studying the effect of glycerol in subcritical and supercritical solvents

Summary

Introduction

Glycerol was first isolated by the Swedish chemist: Carl W. Glycerol or propane-1,2,3-triol 1 is produced in large quantities as a byproduct in many industries [3,4,5]. The large-scale production of biodiesel from fats, where glycerol is a waste product, has made glycerol a highly economic solvent and reactant [6,7,8,9,10,11,12] This has attracted many researchers in the last two decades to find routes for converting this surplus into value added products [13,14,15,16,17,18,19,20,21,22,23,24]. Some of glycerol’s utilities in chemical industries are summarized in Scheme 1

Methods

Results

Conclusion