344-04-7Relevant articles and documents
Diazotization of pentafluoroaniline by means of anion-catalyzed phase transfer catalysis in a hydrophobic organic solvent
Iwamoto, Hidetoshi,Sonoda, Takaaki,Kobayashi, Hiroshi
, p. 535 - 537 (1984)
Anion-catalyzed phase-transfer catalysis was successfully applied to diazotization of pentafluoroaniline in a dichloromethane-aqueous sulfuric acid two-phase system.The resulting diazonium group was coupled in situ with anisole, 1-methoxynaphthalene, and mesitylene, and replaced in situ with bromo, hydryl, and phenyl substituents under a two-phase condition.
Thermal electron attachment to C6F5X and C6H5X (X - I, Br, Cl, and F)
Shimamori, Hiroshi,Tatsumi, Yoshitsugu,Suanagawa, Takeyoshi
, p. 7787 - 7792 (1993)
Rate constants have been measured for thermal electron attachment to C6F5X (X = I, Br, Cl, F, and H) and C6H5X (X = I, Br, Cl, and F) at room temperature in N2 buffer gas (1-100 Torr) using the pulse-radiolysis microwave cavity method.For all the compounds studied, the rate constants are of the two-body type.Unexpectedly, the values for C6F5X except C6F5H are all the same (ca. 2 x 10-7 cm3 molecule-1 s-1), which are higher than most of the previous values, while that for C6F5H, measured in Xe and Ar buffer gases, is very low (7 x 10-12 cm3 molecule-1 s-1).For C6H5X, the value decreases dramatically with varying X from I to Br to Cl as 1.0 x 10-8 to 6.5 x 10-12 to 3 x 10-14 cm3 molecule-1 s-1, and that for C6H5F must be much lower than 10-13 cm3 molecule-1 s-1.These results for the magnitude of the rate constant are rationalized by the variation in the energy of a transient negative-ion state of each molecule, which results from a combination of the electron affinities of constituents (halogen atom X and C6F5 radical) and the strength of the C6F5-X (or C6H5-X) bond.
One-pot route to X-perfluoroarenes (X = Br, I) based on FeIII-assisted C-F functionalization and utilization of these arenes as building blocks for crystal engineering involving halogen bonding
Baykov, Sergey V.,Eliseeva, Anastasiya A.,Frontera, Antonio,Galmés, Bartomeu,Kukushkin, Vadim Yu.,Rozhkov, Anton V.
, p. 5908 - 5921 (2020/10/13)
Perfluorinated arenes (benzeneF derivatives, diphenylF, naphthaleneF) were converted into X-perfluoroarenes (X = Br, I) via the developed one-pot protocol based on [Fe(acetylacetonate)3]-assisted C-F functionalization. The syntheses proceed under mild conditions and employ readily available perfluorinated arenes, which are treated with EtMgBr followed by addition of X2/[Fe(acetylacetonate)3] (0.8 mol %); yields range from good to moderate. The σ-hole donor properties of the obtained mono- and di-X-perfluoroarenes and the significance of these species for halogen-bonding-based crystal engineering was illustrated in a series of postsynthetic experiments, all supported by density functional theory (DFT) energy calculations, molecular electrostatic potential (MEP) surface analysis, and the quantum theory of atoms in molecules (QTAIM). These include (i) a solid-state X-ray diffraction study of X-perfluoroarene self-association (dimerization) via iodine σ-hole - electron belt interactions (three X-ray structures) and (ii) verification of X-perfluoroarene σ-hole donor abilities by their interactions with iodides acting as external σ-hole acceptors (five X-ray structures); a Hirshfeld surface analysis was performed for all eight structures.
Preparation method of bromopentafluorobenzene
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Paragraph 0024-0037, (2019/04/06)
The invention relates to a preparation method of bromopentafluorobenzene, and belongs to the technical field of fine chemical synthesis. The method comprises the following steps: preparing bromine chloride through chlorine and bromine in an organic solvent; ensuring that penta fluoro benzene serving as a raw material is in reaction with the bromine chloride in an organic solvent under the existence of a Lewis acid catalyst, so as to form the bromopentafluorobenzene. The method has the advantages that the raw materials are available, the cost is low, unit consumption of bromine is effectively reduced, two bromine in bromine molecule can be sufficiently utilized, the production cost is reduced, and the method has a significance for realizing the scale production of the bromopentafluorobenzene.
Transition-metal-free decarboxylative bromination of aromatic carboxylic acids
Quibell, Jacob M.,Perry, Gregory J. P.,Cannas, Diego M.,Larrosa, Igor
, p. 3860 - 3865 (2018/04/26)
Methods for the conversion of aliphatic acids to alkyl halides have progressed significantly over the past century, however, the analogous decarboxylative bromination of aromatic acids has remained a longstanding challenge. The development of efficient methods for the synthesis of aryl bromides is of great importance as they are versatile reagents in synthesis and are present in many functional molecules. Herein we report a transition metal-free decarboxylative bromination of aromatic acids. The reaction is applicable to many electron-rich aromatic and heteroaromatic acids which have previously proved poor substrates for Hunsdiecker-type reactions. In addition, our preliminary mechanistic study suggests that radical intermediates are not involved in this reaction, which is in contrast to classical Hunsdiecker-type reactivity. Overall, the process demonstrates a useful method for producing valuable reagents from inexpensive and abundant starting materials.
Unexpected reactivity of cyclic perfluorinated iodanes with electrophiles
Gruber, Stefan,Ametamey, Simon M.,Schibli, Roger
supporting information, p. 8999 - 9002 (2018/08/21)
We have found that cyclic perfluorinated iodanes react with electrophiles (E+ = Br, Cl, F, I) to afford perfluorinated E-RF compounds. This reactivity is unexpected since cyclic perfluorinated iodanes are considered as electrophilic reagents that normally react with nucleophiles (e.g. Nu- = SR, OR) to afford Nu-RF products. The utility of this new transformation is demonstrated for a [18F]CF3CF2-containing compound which was prepared from [18F]XeF2 obtained from cyclotron produced [18F]fluoride.
Method for preparing 2,3,4,5,6-pentafluorophenol
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, (2017/08/29)
The invention discloses a method for preparing 2,3,4,5,6-pentafluorophenol. The method comprises the following step of in water, performing an oxidation reaction on 2,3,4,5,6-pentafluoro phenylboronic acid as shown in the formula (VI) and hydrogen peroxide, thereby obtaining 2,3,4,5,6-pentafluorophenol as shown in the formula (VII). According to the method, an oxidation reaction is implemented in the water, so that the method is low in cost, and environmental-friendly; and besides, the method is high in reaction yield and purity and relatively applicable to industrial production.
PROCESS FOR THE PREPARATION OF ORGANIC BROMIDES
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Paragraph 00139, (2017/07/28)
The present invention provides a process for the preparation of organic bromides, by a radical bromodecarboxylation of carboxylic acids with a bromoisocyanurate.
Unexpected distinction in reactivity of pentafluorobenzenesulfonyl halides toward organolithiums and organomagnesium halides
Bardin, Vadim V.,Maksimov, Alexander M.
, p. 731 - 737 (2017/10/16)
C6F5SO2Cl reacts with organolithiums and organomagnesium halides RM (R = Me, Bu, Ph; M = Li, MgX) to give mainly C6F5H and C6F5Cl. C6F5SO2Br and
Mechanical device for preparing bromopentafluorobenzene
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Paragraph 0010-0012, (2017/03/23)
The invention discloses a mechanical device for preparing bromopentafluorobenzene. The mechanical device for preparing bromopentafluorobenzene belongs to the field of fine chemical production machinery. The mechanical device comprises a high-pressure reaction kettle (1), a chemical reaction kettle (2) and a reduced-pressure distiller (3). The mechanical device is characterized in that a pentafluorobenzoic acid inlet (4), a water inlet (5) and a waste liquid outlet (6) are arranged on the high-pressure reaction kettle (1); a first material slurry pump and pipeline (7) is arranged between the high-pressure reaction kettle (1) and the chemical reaction kettle (2); a bromine water inlet (8), a sodium sulfate aqueous solution inlet (9) and a waste liquid outlet (10) are arranged on the chemical reaction kettle (2); a second material slurry pump and pipeline (11) is arranged between the chemical reaction kettle (2) and the reduced-pressure distiller (3); a steam outlet (12) is arranged on the reduced-pressure distiller (3); and a final-product outlet (13) is arranged on the reduced-pressure distiller (3).
