Simple and Efficient Method for Acetylation of Alcohols, Phenols, Amines, and Thiols Using Anhydrous NiCl₂ Under Solvent-Free Conditions

Abstract

Solvent-free acetylation of alcohols, phenols, amines, and thiols with acetic anhydride (Ac₂O) in the presence of 0.1 mol% (13 mg) anhydrous NiCl₂, an inexpensive and easily available catalyst. Excellent yields, short reaction time, and mild reaction conditions are important features of this method.

Keywords:

• Acetic anhydride
• acetylation
• anhydrous NiCl₂
• solvent-free

ACKNOWLEDGMENT

The authors acknowledge the partial support of this work by Prof. B. P. Bandgar, Vice chancellor, University of Solapur, India.

Notes

^a Isolated yield of the corresponding acetylated product.

^a The substrate was treated with 1 equiv. of the anhydride in the presence of 0.1 mol% (13 mg) of catalyst under solvent-free conditions at room temperature.

^b Isolated yield of the corresponding acetylated product.

^a Yields refer to pure products. All products were characterized by comparison of their IR spectra, ¹H NMR spectra, and elemental analysis with those of authentic samples.