Synthesis of 3,4,5,6‐Tetrahydro‐2H‐1,3,4‐oxadiazin‐2‐ones Employing a Metal Hydride and Diethyl Carbonate: An Alternative Cyclization Method over 1,1′‐Carbonyldiimidazole

Abstract

A series of 3,4,5,6‐tetrahydro‐2H‐1,3,4‐oxadiazin‐2‐ones have been synthesized from valine, leucine, ephedrine, and norephedrine. The synthesis is accomplished through a process of nitrosation, reduction, and cyclization. The cyclization protocol employed involves the use of a metal hydride (LiH or NaH) and diethyl carbonate rather than 1,1′‐carbonyldiimidazole.

Keywords:

• 3,4,5,6‐Tetrahydro‐2H‐1,3,4‐oxadiazin‐2‐ones cyclization
• 1,1′‐Diethylcarbonate
• β‐Amino alcohols
• Oxadiazinone

Acknowledgment

We gratefully acknowledge the financial support from the department of chemistry of Illinois State University (ISU). We also acknowledge continued support from Merck & Co, Inc.