A preparative method was developed for the synthesis of 5-fluoro-substituted pyrazoles by the reaction of fluoroolefins with substituted hydrazines in the presence of triethylamine. The fluorine atom at the C5 position of the pyrazoles obtained is readily substituted by O-, N-, and S-nucleophiles with the formation of 5-alkoxy-, amino-, mercapto-substituted fluoroalkylpyrazoles.
A preparative method was developed for the synthesis of 5-fluoro-substituted pyrazoles by the reaction of fluoroolefins with substituted hydrazines in the presence of triethylamine. The fluorine atom at the C5 position of the pyrazoles obtained is readily substituted by O-, N-, and S-nucleophiles with the formation of 5-alkoxy-, amino-, mercapto-substituted fluoroalkylpyrazoles.
[EN] PROCESS FOR THE PREPARATION OF 5-FLUORO-1H-PYRAZOLES STARTING FROM HEXAFLUOROPROPENE<br/>[FR] PROCÉDÉ DE PRÉPARATION DE 5-FLUORO-1H-PYRAZOLES À PARTIR D'HEXAFLUOROPROPÈNE
申请人:BAYER CROPSCIENCE AG
公开号:WO2015181139A1
公开(公告)日:2015-12-03
A new process for the preparation of 5-fluoro-1H-pyrazoles of the general formula (I)as described herein and further reactions with this compound.
这里描述了一种制备通式(I)中5-氟-1H-吡唑的新工艺,以及与该化合物的进一步反应。
[EN] PROCESS FOR THE PREPARATION OF 5-FLUORO-1H-PYRAZOLES<br/>[FR] PROCÉDÉ POUR LA PRÉPARATION DE 5-FLUORO-1H-PYRAZOLES
申请人:BAYER CROPSCIENCE AG
公开号:WO2015078846A1
公开(公告)日:2015-06-04
A new process for the preparation of 5-fluoro-1H-pyrazoles of the general formula (I) as described herein, resulting from the reaction of an olefin with hydrazine in the presence of water and a base.
[EN] PROCESS FOR THE PREPARATION OF 5-FLUORO-1H-PYRAZOLES<br/>[FR] PROCÉDÉ DE PRÉPARATION DE 5-FLUORO-1H-PYRAZOLES
申请人:BAYER CROPSCIENCE AG
公开号:WO2015078847A1
公开(公告)日:2015-06-04
A new process for the preparation of 5-fluoro-1H-pyrazoles of the general formula (I) as described herein comprising reacting an olefin with an hydrazine.
本文描述了一种制备通式(I)中的5-氟-1H-吡唑的新工艺,包括将烯烃与肼反应。
PROCESS FOR THE PREPARATION OF 5-FLUORO-1H-PYRAZOLES
申请人:BAYER CROPSCIENE AG
公开号:US20150152062A1
公开(公告)日:2015-06-04
A new process for the preparation of 5-fluoro-1H-pyrazoles of the general formula (I)
is described, resulting from the reaction of an olefin of the general formula (II)
with hydrazines of the formula (III)
R
1
—NH—NH
2
(III),
wherein
R
1
is selected from C
1
-C
6
alkyl, C
5
-C
10
aryl;
R
2
is a trihalomethyl moiety with at least one fluorine atom; and
R
3
is selected from C
1
-C
5
haloalkyl, CF
3
, C
2
F
5
, C
3
F
7
, CF
2
CF
2
Cl, CFClCF
3
,
in the presence of water and a base.
Synthesis of fluorinated N-arylpyrazoles with perfluoro-2-methyl-2-pentene and arylhydrazines
作者:Ki-Whan Chi、Sung-Jun Kim、Tae-Ho Park、Yurii V. Gatilov、Irina Yu. Bagryanskaya、Georgii G. Furin
DOI:10.1016/s0022-1139(99)00079-2
日期:1999.8
Reactions of arylhydrazines (phenyl, 2-nitrophenyl, 4-nitrophenyl, 2,4-dinitrophenyl, pentafluorophenyl, 4-trifluoromethyl-2,3,5,6-tetrafluorophenylhydrazine or 4,4'-dihydrazinooctafluorobiphenyl) with perfluoro-2-methyl-2-pentene in the presence of triethylamine have effectively produced 1-aryl-perfluoro-3-ethyl-4-methylpyrazole and 1-aryl-perfluoro-5-ethyl-4-methylpyrazole in various ratios depending on the reaction conditions and arylhydrazine used. Syn- and anti-aminoimines which might be the intermediates for pyrazoles have been isolated under appropriate conditions. The routes of formation for these products and the role of triethylamine have been discussed. The reaction of perfluoro-2-methyl-2-pentene with phenylhydrazine has been investigated in detail. The structure of 3-fluoro-5-pentafluoroethyl-1-phenyl-4-trifluoromethylpyrazole has been elucidated by X-ray crystallography. (C) 1999 Elsevier Science S.A. All rights reserved.