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

Journal of Heterocyclic Chemistry

Volumn 39, Issue 5, 2002, Pages 1025-1027

  Pavlik, James W ^a   Na Ayudhya, Theppawut Israsena ^a   Tantayanon, Supawan ^b  

^a Life Science and Bioengineering Center   (United States)

^b CHULALONGKORN UNIVERSITY   (Thailand)

Author keywords

[No Author keywords available]

Indexed keywords

1 METHYL 3 (TRIFLUOROMETHYL)PYRAZOLE; 1 METHYL 5 (TRIFLUOROMETHYL)PYRAZOLE; 4 ETHOXY 1,1,1 TRIFLUORO 3 BUTEN 2 ONE; 4,5 DIHYDRO 1 METHYL 5 (TRIFLUOROMETHYL)PYRAZOL 5 OL; ACID; ALCOHOL; FLUORINE DERIVATIVE; METHYLHYDRAZINE; PYRAZOLE DERIVATIVE; UNCLASSIFIED DRUG;

ARTICLE; CATALYSIS; DEHYDRATION; POLYMERIZATION;

EID: 0036746878     PISSN: 0022152X     EISSN: None     Source Type: Journal    
DOI: 10.1002/jhet.5570390526     Document Type: Article

References (9)

1. M. E. F. Braibante, G. Clar, and M. A. P. Martins, J. Heterocyclic Chem., 30, 1159 (1993).
2. H. G. Bonacorso, A. D. Wastowski, N. Zanatta, and M. A. P. Martins, Synth. Commun., 30, 1457 (2000).
3. A. Colla, M. A. P. Martins, G. Clar, S. Krimner, and P. Fischer, Synthesis, 483 (1991).
4. Commercially available absolute ethanol was further purified by refluxing over magnesium ethoxide followed by fractional distillation [5].
5. A. Lund and J. Bejerrum, Ber., 64B, 210 (1931).
6. Y. Kamitori, M. Hojo, R. Masuda, M. Fujishiro, and M. Wada, Heterocycles, 38, 21 (1994), See reference 3.
7. J. W. Lyga and R. M. Patera, J. Heterocyclic Chem., 27, 919 (1990).
8. This compound was inexplicably reported in reference 1 to have a melting range of 68-70 C.
9. 1-Methyl-3-(trifluoromethyl)pyrazole (6) and 4,5-dihydro-1-methyl-5-(trifluoromethyl)pyrazol-5-ol (4) could also be separated by column chromatography on silica gel. Elution with ethyl acetate (10%)-hexane (90%) gave 6 (first fraction) and 4 (second fraction) in yields of 6% and 23% respectively.