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Synthesis and 13 C NMR of (trifluoromethyl)hydroxypyrazoles
Author(s) -
Lee Len F.,
Schleppnik Francis M.,
Schneider Ronald W.,
Campbell Dwane H.
Publication year - 1990
Publication title -
journal of heterocyclic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.321
H-Index - 59
eISSN - 1943-5193
pISSN - 0022-152X
DOI - 10.1002/jhet.5570270224
Subject(s) - trifluoromethyl , chemistry , methylhydrazine , pyrazole , carbon 13 nmr , nmr spectra database , fluorine 19 nmr , nuclear magnetic resonance spectroscopy , medicinal chemistry , proton nmr , stereochemistry , organic chemistry , spectral line , alkyl , physics , astronomy , phenylhydrazine
Reaction of ethyl 4,4,4‐trifluoroacetoacetate with methylhydrazine produced not only the previously reported 5‐hydroxy‐3‐(trifluoromethyl)pyrazole 1 but also its unknown isomer the 3‐hydroxy‐5‐(trifluoromethyl)pyrazole 4 . The structure assignments are established based on 13 C nmr spectra. Compound 1 was converted to 5‐chloro‐3‐(trifluoromethyl)pyrazolecarboxylic acid 3 in two steps.