A simple process for the preparation of pralidoxime chloride

431-435Pralidoxime chloride (2-PAM chloride) is an important drug included in National List of Essential Medicines-2003 for treating pesticide poisoning. However, the current methods for its preparation use hazardous methyl halides such as methyl chloride or methyl iodide. In the present work, reaction of pyridine-2-aldoxime with methyl methanesulfonate in acetonitrile gave 2-PAM mesylate in high yields (90%). Use of methyl tosylate in toluene resulted in 2-PAM tosylate (90% yield). Both 2-PAM mesylate and 2-PAM tosylate on treatment with dry hydrogen chloride in isopropanol, resulted in 2-PAM chloride in high yields (90%) and purity (>99%)