Minimizing side reactions in classical pyrazole synthesis from β-oxonitriles: The use of acetylhydrazine

Letters in Organic Chemistry

Volumn 5, Issue 7, 2008, Pages 594-598

  Krasavin, Mikhail ^a,b   Konstantinov, Igor O ^a  

^a Chemical Diversity Research Institute   (Russian Federation)

^b TULA STATE LEV TOLSTOY PEDAGOGICAL UNIVERSITY   (Russian Federation)

Author keywords

3 oxoalkanenitriles; Acetylhydrazine; Aminopyrazoles; Kilogram scale; Process chemistry

Indexed keywords

EID: 57349191195     PISSN: 15701786     EISSN: None     Source Type: Journal    
DOI: 10.2174/157017808785982266     Document Type: Article

References (17)

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15. 6) δ 1.38 (s, 9H), 3.68-4.25 (m, 4H), 5.02 (broad s, 2H), 12.15 (broad s, 1H).
16. 4, filtered, and concentrated in vacuo to provide a solid residue (80-90% rich in the target compound). Crystallization from isopropyl alcohol provided analytically pure material.
17. 6) δ 3.56 (s, 3H), 4.42 (br s, 2H), 5.75 (s, 1H), 6.42 (s, 1H), 7.17-7.26 (m, 2H), 7.52 (m, 1H),7.83 (m, 1H), 11.12 (br s, 1H); LCMS (M+H) 213.