Clay Catalysts in Organic Synthesis

Introduction

Clay minerals are made up of layered silicates. They are crystalline materials of very fine particle size ranging from 150 to less than 1 micron. There are two basic building blocks - tetrahedral and octahedral layers, which are common to clay minerals. [1]

A variety of organic reactions that are catalysed by Brønsted acids such as H₂SO₄, HCl, and other protonic acids or Lewis acids such as AlCl₃, FeCl₃, etc. have been shown to take place in clays, especially montmorillonite, more efficiently, i.e., under milder conditions, with greater selectivity, better yields, shorter reaction times and so on. The range of reactions that have been successfully performed on clay catalysts includes addition, dehydration, elimination, oxidation, rearrangement reactions, substitution, etc. [2]

References

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