Solvent-Free Acylation of Alcohols, Phenols, Thiols and Amines

The hazardous and toxic nature of many solvents, in particular organic solvents that are extensively used in large scale for organic reactions have transformed a serious threat to the environment. Therefore, the design of solvent-free catalytic reaction has received considerable attention during recent times in the field of green synthesis. A solvent-free or solid state reaction may be accomplished using the reactants single or merge them in clays, zeolites, silica, alumina or other substrates. Esters, thioesters and amides are important and valuable compounds in the area of industry, medicine, pharmaceutical and heterocyclic chemistry. In this paper, various solvent-free systems to synthesize esters, thioesters and amides via the acylation of alcohols, phenols, thiols and amines are described. In this review we summarized the activities presented mainly the recent years.