Mild and Useful Method for N-Acylation of Amines

Abstract

Iodine is found to promote quantitative N-acylation of primary and secondary amines (aliphatic and aromatic) in a very short time with an equimolar amount of acetyl chloride and benzoyl chloride under solvent-free conditions at room temperature. This catalytic acylation of amines offers an additional useful method for the acetylation using acetyl chloride instead of acetic anhydride and other acetylating agents. This method is also useful in the N-acylation of heterocycles. Mild reaction condition, high selectivity, efficiency, and good yields are some of the major advantages of the procedure.

Keywords:

• Acetamide
• acetyl chloride
• N-acylation
• benzamides
• benzoyl chloride
• iodine

Notes

^a Reaction condition: substrate = 1 mmol, AcCl = 1.05 mmol, iodine = 0.1 mmol, 25°C.

^b Products have been characterized by melting points, chemical tests, IR, and ¹H NMR data.

^c Isolated yield.

^d AcCl (3.5 eq) was used.

^a Reaction condition: substrate = 1 mmol, PhCOCl = 1.05 mmol, iodine = 0.1 mmol, 25°C.

^b Products have been characterized by melting points, chemical tests, IR, and ¹H NMR data.

^c Isolated yield.

^d AcCl (3.5 eq) was used.