A novel and efficient synthesis of 2,5-substituted 1,2,4-triazol-3-ones |
| |
Authors: | James Zhengwu Deng Christopher S Burgey |
| |
Institution: | Department of Medicinal Chemistry, Merck Research Laboratories, PO Box 4, West Point, PA 19486, USA |
| |
Abstract: | A novel procedure for preparing 1,2,4-triazol-3-ones is described. Various alkyl, aryl, and heterocyclic groups were introduced successfully at both the N2 and C5 positions. The triazolone ring was constructed through an intramolecular cyclization of a novel acyclic precursor, which in turn was synthesized by treating a mono protected hydrazine with an acyl isocyanate. Under conditions that remove the hydrazine protecting group, the intramolecular cyclization occurs rapidly, to deliver the 2,5-substituted 1,2,4-triazol-3-ones in excellent yields (79-99%) without column purification. |
| |
Keywords: | Tiazolone Heterocycles Hydrazine Acyl isocyanate |
本文献已被 ScienceDirect 等数据库收录! |
|