Deep Eutectic Solvent Copper salt as a green catalyst for the acetylation of various alcohols, phenols and amines

N-methylpyrrolidonium-Cu chloride based deep eutectic solvent (NMPCuClDES) was synthesized. This DES was characterized by XRD, FT-IR and NMR techniques for their surface area, surface acidity, crystallinity and functionality. The catalytic activity of DES was determined in acetylation of various alcohols, phenols and amines with acetic anhydride. The reaction conditions were optimized by varying the parameters such as molar ratio of the reactants, reaction temperature and amount of the DES. The DES catalyst can also be reused for acetylation at least for five reaction cycles without any appreciable loss of catalytic activity. The acetylation of alcohols, phenols and amines is one of the most important reactions. This reaction used for transformations in organic synthesis, especially in the synthesis of natural compounds and biological activity compounds [1]. The protection of such functional groups are often necessary during the course of various transformations in a synthetic sequence, particularly in the construction of polyfunctional molecules such as nucleosides, carbohydrates, steroids and natural products [2]. These reactions were carried out using acetylating agent and inorganic acids catalysts such as chloride acid or AlCl3, BF3. An important disadvantage of most existing methodologies is the use of high acidic, high temperatures, stoichiometric amount of catalyst, long reaction times and low yields. Therefore, introduction of new methods and catalysts for the preparation of esters is still in demand. The present method has the additional advantages of mild conditions, high yield, easy separation and environmentally friendly catalysts.