Condensation of methylhydrazine with 4-ethoxy-1,1,1-trifluoro-3-buten-2-one. A reinvestigation

✍ Scribed by James W. Pavlik; Theppawut Israsena Na Ayudhya; Supawan Tantayanon

• Publisher: Journal of Heterocyclic Chemistry
• Year: 2002
• Tongue: English
• Weight: 29 KB
• Volume: 39
• Category: Article
• ISSN: 0022-152X
• DOI: 10.1002/jhet.5570390526

✦ Synopsis

Abstract

In contrast to previous reports, 4‐ethoxy‐1,1,1‐trifluoro‐3‐buten‐2‐one (1) was observed to react with methylhydrazine (2) in refluxing ethanol to yield 1‐methyl‐3‐(trifluoromethyl)pyrazole (6) and 4,5‐dihydro‐1‐methyl‐5‐(trifluoromethyl)pyrazol‐5‐ol (4). The later compound undergoes acid catalyzed dehydration to 1‐methyl‐5‐(trifluoromethyl)pyrazole (3).