- Rapid aerobic iodination of arenes mediated by hypervalent iodine in fluorinated solvents
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Arenes are rapidly converted to the corresponding iodides by aerobic oxidative iodination at room temperature by treatment with iodine and catalytic quantities of nitrous acid in a fluorinated solvent. Dichloroiodic acid is proposed as the actual iodination reagent.
- Iskra, Jernej,Murphree, S. Shaun
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- Synthesis and structure of a novel alkynyl-containing disulfide compound as cathode materials for secondary lithium batteries
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A novel alkynyl-containing disulfide compound, 5,8-dihydro-1H,4H-2,3,6,7- tetrathia-anthracen (TMSEDTTA), was synthesized. The structures of the target compound and the intermediates have been identified by 1H NMR, 13C NMR, mass spectrometry, Fourier-transform infrared, Raman spectra, X-ray photoelectron spectroscopy, and elemental analysis. In addition, the structure of (Z)-(1,2-dibromo-2-(2,3,5,6-tetrakis(bromomethyl)phenyl)vinyl) trimethylsilane (5) was determined by single X-ray analysis. Taylor and Francis Group, LLC.
- Jin, Zuxi,Lu, Yunguo,Li, Shixi,Li, Zaoying
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- A Mild and Convenient Procedure for Conversion of Aromatic Compounds into Their Iodides Using Ammonium Hexanitratocerate(IV)
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Polymethylbenzenes, polymethoxybenzenes, and naphthalene are iodinated with tetrabutylammonium iodide, alkali metal iodides, or molecular iodine in the presence of ammonium hexanitrocerate(IV).Ammonium hexanitrocerate(IV) behaves as a catalyst in the latter system, whereas it is a reagent in the former two.
- Sugiyama, Takashi
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- Regioselective iodination of activated arenes using phenyl trimethylammonium dichloroiodate in ionic liquid under microwave irradiation
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The regioselective iodination of activated arenes has been achieved in the presence of phenyltrimethylammonium dichloroiodate and ionic liquid. The reaction has been carried out by both conventional heating as well as by microwave irradiation. Copyright Taylor & Francis, Inc.
- Tilve, Rutuja D.,Kanetkar, Vinod R.
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- Iodine(I) reagents in hydrochloric acid-catalyzed oxidative iodination of aromatic compounds by hydrogen peroxide and iodine
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Hydrochloric acid activates the oxidative iodination of aromatic compounds with the iodine- hydrogen peroxide system through the formation of an iodine(I) compound as the iodinating reagent. Activation with hydrochloric acid is more powerful than that with sulfuric acid. The formation of dichloroiodic(I) acid (HICl2) with various forms of hydrogen peroxide was followed using UV spectroscopy. The HICl2 was used as the iodinating reagent. In the preparative oxidative iodinaton of various aromatic compounds, hydrochloric acid was used in a catalytic amount and the iodine(I) reagent was formed in situ with 0.5 equiv. hydrogen peroxide and 0.5 equiv. molecular iodine. Two types of reactivity were observed in oxidative iodination with iodine(I) species catalyzed by hydrochloric acid: in the iodination of anisole 1a better yields of iodination were observed with a smaller amount of hydrochloric acid, while on the contrary 4-tert-butyltoluene 1b gave better yields of iodination upon increasing the amount of hydrochloric acid. Reactivity was further manipulated by the choice of the solvent (MeCN, trifluoroethanol, hexafluoro-2-propanol). Copyright
- Bedrac, Leon,Iskra, Jernej
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supporting information
p. 1243 - 1248
(2013/06/27)
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- Potassium 4-iodylbenzenesulfonate: Preparation, structure, and application as a reagent for oxidative iodination of arenes
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A new hypervalent iodine(V) compound, potassium 4-iodylbenzenesulfonate, was prepared by the oxidation of 4-iodobenzensulfonic acid with Oxone in water. This potassium salt can be further converted into 4-iodylbenzenesulfonic acid by treatment with the acidic form of Amberlyst 15 in water. A single-crystal X-ray structure of potassium 4-iodylbenzenesulfonate revealed the presence of polymeric chains in the solid state due to a combination of numerous intra- and intermolecular interactions. Potassium 4-iodylbenzenesulfonate will likely find many practical applications as a thermally stable and water-soluble hypervalent iodine-based oxidant, particularly useful as a reagent for oxidative iodination of aromatic substrates. This reagent can be effectively recovered from the reaction mixture (92 % recovery) by treatment of the aqueous layer with Oxone at 60°C for 2 h, followed by filtration of the precipitate. A new hypervalent iodine(V) compound, potassium 4-iodylbenzenesulfonate, was prepared by oxidation of 4-iodobenzenesulfonic acid with Oxone in water. This new reagent promises many practical applications as a thermally stable, water-soluble and recyclable hypervalent iodine oxidant, particularly useful for oxidative iodination of aromatic substrates.
- Yusubov, Mekhman S.,Yusubova, Roza Y.,Nemykin, Victor N.,Maskaev, Andrey V.,Geraskina, Margarita R.,Kirschning, Andreas,Zhdankin, Viktor V.
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p. 5935 - 5942,8
(2020/09/02)
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- Solvent-free iodination of arenes using iodine-silver nitrate combination
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A simple and environmentally safe general method of iodination of aromatic substrates under sovent-free conditions using the I2/AgNO3 combination in a solid state is reported. Both activated and deactivated aromatic compounds afford the respective aryl iodides in generally high yields (80-90%). Copyright Taylor & Francis Group, LLC.
- Yusubov, Mekhman S.,Tveryakova, Elena N.,Krasnokutskaya, Elena A.,Perederyna, Irina A.,Zhdankin, Viktor V.
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p. 1259 - 1265
(2008/02/01)
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- 1,3-Diiodo-5,5-dimethylhydantoin-An efficient reagent for iodination of aromatic compounds
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1,3-Diiodo-5,5-dimethylhydantoin in organic solvents successfully iodinates alkylbenzenes, aromatic amines, and phenyl ethers. The reactivity of electrophilic iodine is controlled by acidity of the medium. Superelectrophilic iodine generated upon dissolution of 1,3-diiodo-5,5-dimethylhydantoin in sulfuric acid readily reacts with electron-deficient arenes at 0 to 20°C with formation of the corresponding iodo derivatives in good yields. The structure of electrophilic iodine species generated from 1,3-diiodo-5,5- dimethylhydantoin in sulfuric acid is discussed.
- Chaikovskii,Filimonov,Funk,Skorokhodov,Ogorodnikov
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p. 1291 - 1296
(2008/03/27)
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- One-pot preparation of arylalkynes by a tandem catalytic iodination of arenes and palladium-catalyzed coupling of iodoarenes with terminal alkynes
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Iodination of activated arenes by air-oxidation is carried out in the presence of catalytic bismuth salts at room temperature. Subsequently, the formed iodoarenes react with terminal alkynes to give arylalkynes under a selected palladium-catalyzed coupling condition in the same pot.
- Wan, Shun,Wang, Sunewang R.,Lu, Wenjun
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p. 4349 - 4352
(2007/10/03)
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- Comparative study of the reactivity of iodinating agents in solution and solid phase
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The results of reactions of a series of aromatic substrates with iodine, iodine(I) chloride, and N-iodosuccinimide in solution and solid phase were compared for the first time. In all cases, the general relations holding in the iodination process were similar. Iodine(I) chloride was found to chlorinate anthracene. A high efficiency of solid-phase iodination of β-diketones was demonstrated using dibenzoylmethane as an example.
- Krasnokutskaya,Lesina,Gorlushko,Filimonov
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p. 855 - 859
(2007/10/03)
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- Solid-phase iodination of arenes with the system iodine-diacetoxy(phenyl)- λ3-iodane
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The system iodine-diacetoxy(phenyl)-λ3-iodane in the solid phase is capable of iodinating activated arenes.
- Krasnokutskaya,Trusova,Filimonov
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p. 1750 - 1751
(2007/10/03)
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- Solvent-Free Iodination of Arenes at Room Temperature
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Silica supported bismuth(III)nitrate pentahydrate [BNP-SiO2] was prepared under simple co-grinding condition. The iodination of aromatic compounds using BNP-SiO2 and molecular iodine under solvent-free conditions is described. The reaction occurred in the solid state at room temperature, yielding the corresponding mono-iodo derivative in good yields. However, less activated aromatics required longer reaction time with comparatively less yield.
- Alexander, Varughese M.,Khandekar, Amit C.,Samant, Shriniwas D.
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p. 1895 - 1897
(2007/10/03)
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- Selective and effective iodination of alkyl-substituted benzenes with elemental iodine activated by Selectfluor F-TEDA-BF4
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Selective direct introduction of an iodine atom into alkyl-substituted benzene derivatives was effectively achieved by reaction of target molecules with elemental iodine in the presence of 1-chloromethyl-4-fluoro- 1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate) (Selectfluor F-TEDA-BF4). The number of iodine atoms introduced could be modulated by the molar ratio between substrate, iodine and F-TEDA-BF4.
- Stavber, Stojan,Kralj, Petra,Zupan, Marko
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p. 598 - 600
(2007/10/03)
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- 2,4,6,8-tetraiodo-2,4,6,8-tetraazabicyclo[3.3.0]octane-3,7-dione as a mild and convenient reagent for iodination of aromatic compounds
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2,4,6,8-Tetraiodo-2,4,6,8-tetraazabicyclo[3.3.0]octane-3,7-dione (tetraiodoglycoluril) is a convenient reagent for preparative iodination of benzene, alkylbenzenes, polycyclic hydrocarbons, aromatic amines, and phenol ethers in organic solvents under mild conditions.
- Chaikovski,Filimonov,Yagovkin,Ogorodnikov
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p. 2411 - 2415
(2007/10/03)
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- Aromatic iodination: A new investigation on the nature of the mechanism
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Following a suggestion by the late Lennart Eberson, we have employed the ICl-HFP (HFP being hexafluoropropan-2-ol) system in iodination reactions, and found unambiguous evidence for the occurrence of an ET-mechanism of halogenation. The evidence is based on the use of 'intelligent' substrates, which make it possible to fix the boundaries between the occurrence of an ET-mechanism and of a conventional polar mechanism. In an 'intelligent' substrate, in fact, the nature of the product(s) changes significantly depending on the operating mechanism. The ICl-HFP combination is instrumental to the onset of a one-electron oxidation with electron-rich substrates, followed by halogenation. The most prominent example is that of the electron-rich substrate durene (1,2,4,5-tetramethylbenzene, DUR), when compared to mesitylene (1,3,5-trimethylbenzene, MES): with a 'conventional' iodination system (i.e., I2/ Ag+) and in common solvents, where the polar mechanism holds, durene is less reactive (kMES/kDUR = 46 ± 3), but becomes more reactive (kMES/kDUR = 0.23) in HFP with ICl, where the ET-mechanism takes over. Other substrates also support the onset of ET-pathways in HFP. Finally, a preliminary survey of a biohalogenation reaction induced by laccase indicates the modest occurrence of a polar process of iodination with a few substrates.
- Fabbrini, Maura,Galli, Carlo,Gentili, Patrizia,Macchitella, Daniele,Petride, Horia
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p. 1516 - 1521
(2007/10/03)
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- Iodination of aromatic compounds with iodine monochloride in aqueous sulfuric acid
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Iodine monochloride in aqueous sulfuric acid turned out to be a convenient and general reagent for preparative iodination of alkylbenzenes, phenol ethers, and aromatic amines. The relative selectivity and activity of iodine monochloride in aqueous solutions of sulfuric acid with various concentrations were determined using toluene as model substrate. Raising the sulfuric acid concentration results in considerable increase of the electrophilicity of ICl. Effective sulfuric acid concentrations were determined for specific substrate series. Iodine monochloride in aqueous sulfuric acid shows enhanced selectivity in the synthesis of monoiodo derivatives.
- Chaikovskii,Filimonov,Kharlova,Chernova,Sharapova
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p. 666 - 670
(2007/10/03)
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- Enantioselective synthesis of the chromane moiety of vitamin E
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Several new approaches for the enantioselective synthesis of the chromane moiety of vitamin E are described. Sonogashira coupling of 3a with the alkyne 4 and subsequent elimination gave 6, which was bis(hydroxylated) in 93% yield and with 85% ee. Recrystallization gave enantiopure 7a, which was hydrogenated and transformed into the vitamin E precursor 11. The bis(hydroxylation) of 18 and 21 to give 9 and 22, respectively, was less than satisfactory, proceeding with ee values of 28% and 18%. In contrast, stereoselective allylation of ketone 15 followed by removal of the protecting group or ozonolysis of the allyl moiety furnished the allyl alcohol 26 and the aldehyde 27, respectively, in almost enantiopure form, which again could be used as precursors for vitamin E. Partial hydrogenation of 5a gave the alkene 32a and that of 28 the alkene 30b, both of which show interesting atropisomerism.
- Tietze, Lutz F.,Goerlitzer, Jochen,Schuffenhauer, Ansgar,Huebner, Matthias
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p. 1075 - 1084
(2007/10/03)
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- Study of a system I2-NO3 in acetic acid as convenient reagent for iodination of arenes and carbazoles
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Iodine in the presence of sodium, potassium, and calcium nitrates in acetic acid efficently iodinates activeted arenes and carbazoles. The oxygen was shown not to be an indispensible reaction component. A scheme was suggested describing I+ generation in the system via a series of redox processes with participation of NO-3.
- Yusubov,Perederina,Filimonov,Jin, Ho-Whan,Chi, Ki-Whan
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p. 1191 - 1195
(2007/10/03)
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- Solid-state organic reactions proceeding by pulverization: Oxidation and halogenation with iodosobenzene and inorganic solid-supports
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Pulverization-activation method was employed to accelerate solid-state organic reactions. Crushing and grinding of solid mixtures of hydrogen halide-treated silica gels, iodosobenzene and organic substrates in the absence of a solvent brought about smooth and rapid reactions to give halogenated and/or oxidized products in good yields. Various sulfides were smoothly converted to sulfonyl chlorides in one step in excellent yields. The surface of silica gel activated by pulverization serves as a reaction field on which reagent molecules can effectively encounter with each other.
- Sohmiya, Hajime,Kimura, Takahide,Fujita, Mitsue,Ando, Takashi
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p. 13737 - 13750
(2007/10/03)
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- Aromatic Iodination: Evidence of Reaction Intermediate and of the ?-Complex Character of the Transition State
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The reactivity of the four different procedures of aromatic iodination is compared under the same experimental conditions, and their selectivity toward two substrates in competition, i. e., mesitylene (1,3,5-trimethylbenzene, MES) and durene (1,2,4,5-tetramethylbenzene, DUR), is evaluated.Two of these procedures, namely, S2O82-/I2 and Ce(IV)/I2, present strong oxidizing capacity.Since the same MES/DUR relative reactivity is obtained from the four procedures, it becomes possible to state that a common reactive intermediate, most likely the I+ ion, is generated.The use of the MES/DUR mechanistic probe allows one to describe the reactivity picture of the iodination reaction as one of electrophilic substitution at the aromatic nucleous, with a transition state properly represented in terms of a ?-complex.The radical cation of durene also forms when the iodination is carried out by means of oxidizing agents, but it is solely responsible for the formation of side-chain substitution products and is not involved in the nuclear substitution process.
- Galli, Carlo
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p. 3238 - 3245
(2007/10/02)
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- Solid-State Organic Reactions Proceeding by Pulverization of Inorganic Solid-Supports. Reactions of Iodosobenzene with Unsaturated Hydrocarbons on Acid-Treated Silica Gel
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Pulverization of solid mixtures of hydrogen halide-treated silica gels, iodosobenzene, and alkenes or an alkyne in the absence of a solvent brings about smooth and rapid reaction to give halogenated or oxidized products in good yields.
- Sohmiya, Hajime,Kimura, Takahide,Bauchat, Patrick,Fujita, Mitsue,Ando, Takashi
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p. 1391 - 1392
(2007/10/02)
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- Halogenation Using Quaternary Ammonium Polyhalides. XIV. Aromatic Bromination and Iodination of Arenes by Use of Benzyltrimethylammonium Polyhalides-Zinc Chloride System
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The reaction of arenes with benzyltrimethylammonium tribromide or benzyltrimethylammonium dichloroiodate in acetic acid in the presence of ZnCl2 at room temperature or at 70 deg C gave brome- or iodo-substituted arenes in good yield, respectively.
- Kajigaeshi, Shoji,Kakinami, Takaaki,Moriwaki, Masayuki,Tanaka, Toshio,Fujisaki, Shizuo,Okamoto, Tsuyoshi
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p. 439 - 443
(2007/10/02)
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- IODINATION OF ALKYLBENZENES WITH IODINE AND SILVER NITRITE
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Iodination of alkylbenzenes with iodine and silver nitrite at room temperature gives iodoalkylbenzenes in good yield.
- Sy, Wing-Wah,Lodge, Bruce A.
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p. 3769 - 3772
(2007/10/02)
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- POTASSIUM PERMANGANATE - A CONVENIENT OXIDANT FOR DIRECT IODINATION OF AROMATIC COMPOUNDS.
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The authors propose the use of potassium permanganate for direct iodination of aromatic compounds. They tested an iodination system containing iodine, potassium permanganate, and sulfuric and nitric acids on a large number of aromatic compounds. Experimental results show that it is effective for iodination of benzene, halobenzenes, oxygen-containing arenes, alkylbenzenes, and certain condensed hydrocarbons. Iodide yields are often close to, or even higher than, those obtained with the use of periodic and iodic acids. Potassium permanganate has not been used previously for iodination of aromatic compounds, probably because in absence of additives its activating effect on iodine is very weak. However, the effectiveness of the reaction is raised sharply when sulfuric acid is added to the system. This is due both to the higher degree of ionization of iodine molecules, as the result of which the electrons of the I-I bond become more accessible to the oxidant, and to the higher oxidizing power of potassium permanganate in a strongly acidic medium.
- Chaikovskii,Novikov
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p. 121 - 123
(2007/10/02)
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- Thallium in Organic Synthesis. 58. Regiospecific Intermolecular Oxidative Dehydrodimerization of Aromatic Compounds to Biaryls Using Thallium (III) Trifluoroacetate
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Treatment of a variety of aromatic substrates with thallium(III) trifluoroacetate (TTFA) in trifluoroacetic acid (TFA), or in carbon tetrachloride or acetonitrile containing boron trifluoride etherate, results in smooth, rapid, and direct regiospecific oxidative dehydrodimerization to give symmetrical biaryls in good to excellent yield.The method is particularly useful when applied to substrates in which the ring substituents are either electron donating or mildly electron withdrawing.Aromatic substrates which contain powerful electron-withdrawing groups (CN, COOR, NO2) fail to react.The reaction is postulated to proceed via (a) reaction of TTFA with the aromatic substrate and generation of the radical cation Ar+; (b) reaction of this electrophile with the aromatic substrate; (c) oxidative aromatization of the intermediate thus produced by TTFA.Biaryls can be obtained similarly by oxidation of the same substrates with either mercury(II) trifluoroacetate in TFA containing boron trifluoride, lead(IV) acetate in acetonitrile containing boron trifluoride, iron(III) chloride in methylene chloride, or cobalt(III) fluoride in TFA.Yields in the Hg(II) and Fe(III) reactions are generally inferior to those obtained with TTFA, but those obtained in the Pb(IV) and Co(III) oxidations are in many instances comparable to, or even better than, the TTFA results.The oxidations with Hg(II), Pb(IV), Fe(III), and CO(III) are also postulated to proceed via a radical cation mechanism.
- McKillop, Alexander,Turrell, Andrew G.,Young, Derek W.,Taylor, Edward C.
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p. 6504 - 6512
(2007/10/02)
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