Title: Multigram Synthesis of Fluoroalkyl-Substituted Pyrazole-4-carboxylic Acids.
Authors: Iminov, Rustam T.; Mashkov, Alexander V.; Vyzir, Ivan I.; Chalyk, Bohdan A.; Tverdokhlebov, Anton V.; Mykhailiuk, Pavel K.; Babichenko, Ludmila N.; Tolmachev, Andrey A.; Volovenko, Yulian M.; Biitseva, Angelina; Shishkin, Oleg V.; Shishkina, Svetlana V.
Abstract: Acylation of tert-butyl 3-(methylamino)but-2-enoate with fluorinated acetic acid anhydrides occurred at the enamine carbon atom. The reaction of the resulting tert-butyl 3-(methylamino)-2-(RFCO)but-2-enoates with alkyl hydrazines resulted in mixtures of isomeric pyrazoles that were easily separated by column chromatography. The target fluorinated pyrazole-4-carboxylic acids were obtained on a multigram scale.
Subjects: CHEMICAL synthesis; CARBOXYLIC acids; ORGANIC synthesis; ACYLATION; PYRAZOLES; HETEROCYCLIC compounds synthesis; ANHYDRIDES; ENAMINES; COLUMN chromatography
Publication: European Journal of Organic Chemistry, 2015, Vol 2015, Issue 4, p886
ISSN: 1434-193X
Publication type: Academic Journal
DOI: 10.1002/ejoc.201403295

Multigram Synthesis of Fluoroalkyl-Substituted Pyrazole-4-carboxylic Acids.

Iminov, Rustam T.; Mashkov, Alexander V.; Vyzir, Ivan I.; Chalyk, Bohdan A.; Tverdokhlebov, Anton V.; Mykhailiuk, Pavel K.; Babichenko, Ludmila N.; Tolmachev, Andrey A.; Volovenko, Yulian M.; Biitseva, Angelina; Shishkin, Oleg V.; Shishkina, Svetlana V.