348-61-8Relevant academic research and scientific papers
High-throughput Synthesis and Screening of Iridium(III) Photocatalysts for the Fast and Chemoselective Dehalogenation of Aryl Bromides
Bernhard, Stefan,Connell, Timothy U.,Diluzio, Stephen,Kowalewski, Jakub F.,Kowalewski, Tomasz,Lewis, Jacqueline,Mdluli, Velabo,Yaron, David
, p. 6977 - 6987 (2020)
A high-throughput optical screening method for the photocatalytic activity of a structurally diverse library of 1152 cationic iridium(III) complexes ([Ir(C^N)2(N^N)]+), corresponding to all combinations of 48 cyclometalating (C^N) and 24 ancillary (N^N) ligands, was developed. This rapid assay utilizes the colorimetric changes of a high contrast indicator dye, coumarin 6, to monitor the photo-induced electron transfer from a sacrificial amine donor to the metal complex excited state. The resulting [Ir(C^N)2(N^N)]0 can then reduce an aryl bromide to form the highly reactive aryl radical intermediate. The rate of this reaction is dictated by the molecular structure of both coordinating ligands. Relative reaction rate constants determined via this method correlated closely with 19F NMR measurements obtained using a fluorinated substrate. A simple model that expresses the rate constant as a product of a single ″strength″ parameter assigned to each of the 72 ligands can well account for the 1152 measured rate constants. The best performing complexes exhibit much higher reactivity than the benchmark photocatalysts commonly used in photoredox transformations. The catalysts were also successfully tested for their chemoselectivity. The developed screening methodology can enable generation of the large data sets needed to use modern data science to extract structure-activity relationships.
Three-step regioselective synthesis of 2,3-difluorohalobenzenes using tetrafluoroethylene and buta-1,3-diene as starting building blocks
Egorov, M. P.,Lipkind, M. B.,Nefedov, O. M.,Volchkov, N. V.
, p. 925 - 932 (2021/06/07)
The gas-phase copyrolysis of tetrafluoroethylene and buta-1,3-diene in a flow tube reactor at 490–510 °C gives 3,3,4,4-tetrafluorocyclohex-1-ene, which is selectively converted to 1-bromo- or 1-chloro-2,3-difluorobenzene via intermediate steps of halogenation and dehydrohalogenation.
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.
Reactions of aromatic compounds with xenon difluoride
Bardin,Adonin, N. Yu.
, p. 1400 - 1407 (2016/11/29)
Reactions of substituted benzenes C6H5R (R = Me, F, Cl, Br, CF3, NO2) with xenon difluoride in the presence of boron trifluoride–diethyl ether complex in weakly acidic (1,1,1,3,3-pentafluorobutane) and weakly basic media (acetonitrile) have been studied. These reactions lead to the formation of fluorobenzene derivatives FC6H4R (isomer mixture) together with isomeric difluorobenzenes and fluorinated and non-fluorinated biphenyls. The results have been compared with previously reported data obtained in other solvents using other catalysts.
Bromination of aromatic compounds using an Fe2O 3/zeolite catalyst
Nishina, Yuta,Takami, Keishi
supporting information, p. 2380 - 2383 (2013/02/21)
The catalytic bromination of non-activated aromatic compounds has been achieved using an Fe2O3/zeolite catalyst system. FeBr 3 was identified as the catalytic species, formed in situ from HBr and Fe2O3. The catalyst was easy-to-handle and cost effective and could also be recycled. The reaction system was also amenable to the one-pot sequential bromination/C-C bond formation of benzene.
Method for producing tetrakis ( fluoroaryl) borate-magnesium compound
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, (2008/06/13)
Fluoroaryl magnesium halide is reacted with a boron compound so that a molar ratio of the fluoroaryl magnesium halide to the boron compound is not less than 3.0 and not more than 3.7, so as to produce a tetrakis (fluoroaryl) borate·magnesium compound. With this method, there occurs no hydrogen fluoride which corrodes a producing apparatus and requires troublesome waste water treatment.
PHOTOCHEMICAL BROMINATION OF ARENES. 2. FLUOROBENZENE DERIVATIVES (1)
Bolton, Roger,Owen, Elaine S. E.
, p. 393 - 406 (2007/10/02)
Photochemically induced reaction of fluorobenzene and a range of polyfluorobenzenes, both in an excess of the arene and with fluorotrichloromethane as solvent, gave isolable adducts only with fluorobenzene, the isomeric difluorobenzenes, and in very small yield with 1,3,5-trifluorobenzene.These adducts were identified by combustion analysis, mass spectrometry, and n.m.r. techniques (1H, 13C, 19F).In every case, the expected substitution products accompanied these adducts, and in the more fully fluorinated benzene derivatives substitution was the only process observed.Fluorotrichloromethane encouraged the formation of adducts, but the concurrent formation of substantial amounts of substitution products suggested that adducts are not the necessary precursors of the substitution products, in contrast with other systems.
Polysubstituted derivatives of 10-piperazinodibenzo (b,f) thiepine
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, (2008/06/13)
Polysubstituted derivatives of 10-piperazinodibenzo (b,f) thiepine and processes for the preparation thereof are described. The compositions evidence psychotropic and antimicrobial characteristics and are of low toxicity. The described compounds are of the general formula STR1 wherein R2, R3, R7 and R8 are selected from among hydrogen, fluorine and chlorine atoms, a fluoromethyl group, a methoxy group and a hydroxyl group, at least three of R2, R3, R7 and R8 being other than hydrogen, R being selected from among hydrogen, alkyl or alkylhydroxy groups having from 1-3 carbon atoms, an acyloxyalkyl group having from 8-10 carbon atoms in the acyl moiety and from 2-3 carbon atoms in the alkyl moiety and an ethoxycarbonyl group, m and n representing integers from 0-1 and the bond between the 10 and 11 carbon atoms being either a single or double bond.
