- Preparation method of 3, 4, 5-trifluorobromobenzene
-
The invention relates to a preparation method of 3, 4, 5-trifluorobromobenzene, belongs to the technical field of chemical synthesis, and solves the problem that a byproduct 3, 4, 5-trichloronitrobenzene generated in a process of preparing 3, 4-dichloronitrobenzene by introducing chlorine into parachloronitrobenzene cannot be effectively utilized. The method comprises the step of preparing 3, 4, 5-trifluorobromobenzene by taking 3, 4, 5-trichloronitrobenzene as a raw material. According to the technical scheme provided by the invention, the utilization rate of raw materials and the efficiencyof the process can be improved, and high-value utilization of byproducts is realized.
- -
-
Paragraph 0098-0099; 0106; 0109; 0114; 0117
(2020/12/14)
-
- O-dichlorobenzene with a quinolone drugs for coproduction method of key intermediate
-
The invention relates to the field of methods for preparing medicinal intermediates, in particular to the field of methods for preparing key intermediates of quinolone medicines, and develops a method for coproducing the key intermediates of the quinolone medicines by using o-dichlorobenzene as a raw material. The method comprises the following steps of: nitrifying the o-dichlorobenzene serving as the raw material, and performing distillation, purification and stepwise crystallization to obtain 2,3-dichloronitrobenzene and 3,4-dichloronitrobenzene; performing fluoridation on the 2,3-dichloronitrobenzene to obtain 3-chloro-2-fluoronitrobenzene, performing chlorination to obtain 2,6-dichlorofluorobenzene, performing nitration to obtain 1,3-dichloro-2-fluoro-4-nitrobenzene, and finally performing fluoridation to obtain 2,3,4-trifluoronitrobenzene; and performing fluoridation on the 2,3,4-trifluoronitrobenzene to obtain 3-chloro-4-fluoronitrobenzene, performing chlorination to obtain 1,3-dichloro-4-fluorobenzene, and finally performing acylation reaction on the 1,3-dichloro-4-fluorobenzene and acetylchloride to obtain 2,4-dichloro-5-fluoroacetophenone.
- -
-
Paragraph 0015; 0050-0051
(2017/01/19)
-
- PhenoFluorMix: Practical chemoselective deoxyfluorination of phenols
-
A practical deoxyfluorination with novel deoxyfluorinating reagent PhenoFluorMix, a mixture of N,N'-1,3-bis(2,6-diisopropylphenyl)chloroimidazolium chloride and CsF, is presented. PhenoFluorMix overcomes the challenges associated with hydrolysis of PhenoFluor. PhenoFluorMix does not hydrolyze, is readily available on decagram scale, and is storable in air. In this paper, we demonstrate the practicality of the reagent and exhibit the deoxyfluorination of a variety of phenols and heterocycles.
- Fujimoto, Teppei,Ritter, Tobias
-
supporting information
p. 544 - 547
(2015/03/05)
-
- Large-scale preparation of aromatic fluorides via electrophilic fluorination with functionalized aryl- or heteroarylmagnesium reagents
-
Functionalized aryl- or heteroarylmagnesium reagents, prepared from the corresponding bromides or iodides using halogen-magnesium exchange or direct magnesium insertion in the presence of lithium chloride, reacted smoothly with N-fluorobenzenesulfonimide, (PhSO2)2NF, in the mixed solvent (4:1 CH2Cl2-perfluorodecalin) to give the corresponding aromatic fluorides in moderate to good yields. Georg Thieme Verlag Stuttgart · New York.
- Yamada, Shigeyuki,Knochel, Paul
-
experimental part
p. 2490 - 2494
(2010/09/04)
-
- Convenient electrophilic fluorination of functionalized aryl and heteroaryl magnesium reagents
-
"Chemical Equation Presented" Cive me an "F": Electrophilic fluorination of various aromatic and heteroaromatic Grignard reagents is smoothly performed with (PhSO2)2NF as fluorinating agent in a 4:1 mixture of CH2Cl2/ perfluorodecalin (see scheme). This solvent system allows minimization of most side reactions.
- Yamada, Shigeyuki,Gavryushin, Andrei,Knochel, Paul
-
supporting information; experimental part
p. 2215 - 2218
(2010/06/19)
-
- Efficient synthesis of aryl fluorides
-
Chemical Equation Presented Creating C-F bonds: A novel electrophilic fluorination of aryl and heteroaryl Crignard reagents has been discovered and was used for the efficient synthesis of various aryl fluoride derivatives (see picture; THF = tetrahydrofuran).
- Anbarasan, Pazhamalai,Neumann, Helfried,Beller, Matthias
-
experimental part
p. 2219 - 2222
(2010/06/17)
-
- Preparation process of fluorine substituted aromatic compound
-
A preparation process of a fluorine substituted aromatic compound comprising reacting an alkali metal or alkali earth metal salt of an aromatic compound having a hydroxy group with an organic fluorinating agent is disclosed. As a representative fluorinating agent, a bis-dialkylamino-difluoromethane compound, for example, 2,2′-difluoro-1,3-dimethylimidazolidine, is exemplified. According to the process, an industrially useful fluorinated aromatic compound, for example, a fluorobenzene, a fluorine substituted benzophenone, a fluorine substituted diarylsulfone can be prepared with ease in economy without specific equipment.
- -
-
-
- A process for the preparation of o-chlorofluorobenzene
-
ο-Chlorofluorobenzene is prepared from 1,2,3-trichlorobenzene by partial fluorine exchange to a mixture of 2,6-dichlorofluorobenzene and 2,3-dichlorofluorobenzene followed by selective reduction to a mixture of fluorobenzene, ο-chlorofluorobenzene and 2,3-dichlorofluorobenzene. Each of the components of this latter mixture can be separated by a relatively easy distillation, and each has value as an intermediate in the manufacture of other valuable organic chemicals.
- -
-
-
- AROMATIC FLUORINE CHEMISTRY. PART 5. PREPARATION OF 2,6-DIFLUOROANILINE AND 1,2-DIFLUOROBENZENE
-
The preparation of 2,6-difluoroaniline and 1,2-difluorobenzene from 1,2,3-trichlorobenzene is described.An isomeric mixture of 1-chloro-2,3-difluorobenzene and 2-chloro-1,3-difluorobenzene is obtained from KF exchange on 1,2,3-trichlorobenzene.Selective dechlorination of 1-chloro-2,3-difluorobenzene with H2 and Pd/C catalyst gives 1,2-difluorobenzene. 2,6-difluoroaniline is obtained via ammonolysis of 2-chloro-1,3-difluorobenzene.
- Pews, R. Garth,Gall, James A.
-
p. 379 - 386
(2007/10/02)
-