- The Electrochemical cis-Chlorination of Alkenes
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The first example for the electrochemical cis-dichlorination of alkenes is presented. The reaction can be performed with little experimental effort by using phenylselenyl chloride as catalyst and tetrabutylammoniumchloride as supporting electrolyte, which also acts as nucleophilic reagent for the SN2-type replacement of selenium versus chloride. Cyclic voltammetric measurements and control experiments revealed a dual role of phenylselenyl chloride in the reaction. Based on these results a reaction mechanism was postulated, where the key step of the process is the activation of a phenylselenyl chloride-alkene adduct by electrochemically generated phenylselenyl trichloride. Like this, different aliphatic and aromatic cyclic and acyclic alkenes were converted to the dichlorinated products. Thereby, throughout high diastereoselectivities were achieved for the cis-chlorinated compounds of >95 : 5 or higher.
- Strehl, Julia,Fastie, Cornelius,Hilt, Gerhard
-
supporting information
p. 17341 - 17345
(2021/10/23)
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- Dichlorination of olefins with diphenyl sulfoxide/oxalyl chloride
-
The combination of diphenyl sulfoxide and oxalyl chloride was used to accomplish the dichlorination of olefins, in which chlorodiphenylsulfonium salt generated in situ was proposed to be the real active species as a chloronium ion source.
- Ding, Rui,Huang, Shuai,Wang, Qiyi,Liu, Yongguo,Sun, Baoguo,Tian, Hongyu
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supporting information
p. 2319 - 2330
(2020/07/03)
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- Effective bromo and chloro peroxidation catalysed by tungsten(vi) amino triphenolate complexes
-
Amino triphenolate tungsten(vi) complexes have been prepared and they proved to be efficient catalysts in haloperoxidation reactions using hydrogen peroxide as a terminal oxidant and inorganic sources of halides. In particular, interesting results have been obtained in the challenging chloroperoxidation reactivity (catalyst loading down to 0.05% with TONs up to 900). A comparison among three different metal complexes bearing the same ligand (vanadium(v), molybdenum(vi) and tungsten(vi)) showed much better performances of the last complex both on bromo and chloro peroxidations.
- Badetti, Elena,Romano, Francesco,Marchiò, Luciano,Ta?kesenlio?lu, Sara,Da?tan, Arif,Zonta, Cristiano,Licini, Giulia
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p. 14603 - 14608
(2016/09/28)
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- Organoselenium-catalyzed vicinal dichlorination of unsaturated phosphonates
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Diphenyl diselenide (PhSeSePh) was effective as a pre-catalyst for the vicinal dichlorination of α,β-unsaturated phosphonates with sulfuryl chloride. The reaction conditions were mild and the desired products were formed in up to 93% yield and moderate diastereoselectivity (10:1). The important diphenylselenium dichloride intermediate was obtained and characterized by X-ray crystallography.
- Zeng, Xianghua,Gong, Chunhua,Zhang, Junyong,Xie, Jingli
-
supporting information
p. 7866 - 7871
(2016/09/12)
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- Vicinal dichlorination of olefins using NH4Cl and oxone
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A mild and efficient protocol for the preparation of 1,2-dichloroalkane derivatives from olefins using NH4Cl and Oxone at room temperature is described. A variety of terminal, internal, and cyclic alkenes reacted smoothly to give the corresponding dichlorinated products in good to excellent yields. Moreover, 1,2-disubstituted symmetrical and unsymmetrical olefins dichlorinated with moderate to excellent diastereoselectivity. This method precludes the use of acidic additives and transition metals in the synthesis of vicinal dichlorides.
- Swamy, Peraka,Reddy, Marri Mahender,Kumar, Macharla Arun,Naresh, Mameda,Narender, Nama
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p. 251 - 257
(2014/03/21)
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- Organocatalysis as a safe practical method for the stereospecific dibromination of unsaturated compounds
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Organocatalytic stereospecific dibromination of a wide variety of functionalized alkenes was achieved using a stable, inexpensive halogen source, 1,3-dibromo 5,5-dimethylhydantoin, and a simple thiourea catalyst at room temperature. The presence of a tertiary amine enhanced the rate of the dibromination reaction, and yields were good in various solvents, including aqueous solvents. The procedure was extended to alkynes and aromatic rings and to dichlorination reactions by using the 1,3-dichloro hydantoin derivative.
- Hernandez-Torres, Gloria,Tan, Bin,Barbas, Carlos F.
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supporting information; experimental part
p. 1858 - 1861
(2012/06/18)
-
- Pyridine-assisted chlorinations and oxidations by palladium(IV)
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The reactivity of the bis-NHC complex LPdIVCl4 (L = κ2-[R-NHCCH2NHC-R] with R = C14H 29) in chlorinations and oxidations of organic substrates was considerably increased in the presence of pyridine. For alkene chlorinations, this effect was due to the in situ formation of highly reactive LPd IVCl3(py)+, which was able to transfer Cl + to the C=C bond in a ligand-mediated process (devoid of π complexation), which did not require py dissociation. The enhanced reactivity in the presence of pyridine also extended to the oxidation of secondary and benzylic alcohols under mild conditions in a reaction where py served as a base, broadening the known scope of reactivity for PdIV complexes. LPdIVCl3(py)+ could be formed from Cl -/py exchange or from the oxidation of LPdIICl(py) + by Cl2. Taking advantage of the enhanced reactivities that pyridine coordination imparted on both PdII and PdIV complexes allowed for the catalytic chlorination of styrene with LPd IVCl4 as a sacrificial oxidant, thereby establishing the principal feasibility of PdII/PdIV catalyses that obviates PdII activations of the substrate.
- McCall, A. Scott,Kraft, Stefan
-
scheme or table
p. 3527 - 3538
(2012/06/16)
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- Formation of iron(III) meso-chloro-isoporphyrin as a reactive chlorinating agent from oxoiron(IV) porphyrin π-cation radical
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Iron(III) isoporphyrin, a tautomer of porphyrin with a saturated meso carbon, is one of the isoelectronic forms of oxoiron(IV) porphyrin π-cation radical, which is known as an important reactive intermediate of various heme enzymes. The isoporphyrin has been believed to be incapable of catalyzing oxygenation and oxidation reactions. Here, we report that an oxoiron(IV) porphyrin π-cation radical can be converted to iron(III) meso-chloro- isoporphyrin in the presence of trifluoroacetic acid and chloride ion. More importantly, this study shows the first evidence that iron(III) meso-chloro-isoporphyrin is an excellent reactive agent for chlorinating aromatic compounds and olefins. The results of this study suggest that the mechanism involves electrophilic chlorination of substrate with iron(III) meso-chloro-isoporphyrin.
- Cong, Zhiqi,Kurahashi, Takuya,Fujii, Hiroshi
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supporting information; experimental part
p. 4469 - 4472
(2012/04/23)
-
- Facile preparation and reactivity of polystyrene-supported (dichloroiodo)benzene: A convenient recyclable reagent for chlorination and oxidation
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A facile one-pot preparation of polystyrene-supported (dichloroiodo)benzene (loading of -ICl2 up to 1.35 mmol/g) from polystyrene, iodine, and bleach has been developed. This recyclable reagent is useful for efficient chlorination of organic substrates and selective oxidation of various alcohols to the corresponding carbonyl compounds in high yields under mild conditions. The final products are conveniently separated from the polymeric byproduct by simple filtration and isolated in good purity after evaporation of solvent.
- Chen, Jiang-Min,Zeng, Xiao-Mei,Middleton, Kyle,Zhdankin, Viktor V.
-
supporting information; experimental part
p. 1952 - 1955
(2011/04/25)
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- Oxidation of chloride and subsequent chlorination of organic compounds by oxoiron(IV) porphyrin π-cation radicals
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Ironing it out: Oxoiron(IV) porphyrin π-cation radical complexes (see figure) serve as models for the oxidation of Cl- into an active chlorinating reagent that chlorinates various organic compounds. Evidence suggests that Cl- is oxidized to Cl2 via Cl.. The mechanism involving either direct electron transfer or iron(III) hypochlorite formation, and then homolysis of the Cl-O bond is discussed. Copyright
- Cong, Zhiqi,Kurahashi, Takuya,Fujii, Hiroshi
-
experimental part
p. 9935 - 9939
(2011/12/13)
-
- Bis- N -heterocyclic carbene palladium(IV) tetrachloride complexes: Synthesis, reactivity, and mechanisms of direct chlorinations and oxidations of organic substrates
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This Article describes the preparation and isolation of novel octahedral CH2-bridged bis-(N-heterocyclic carbene)palladium(IV) tetrachlorides of the general formula LPdIVCl4 [L = (NHC)CH 2(NHC)] from LPdIICl2 and Cl2. In intermolecular, nonchelation-controlled transformations LPdIVCl 4 reacted with alkenes and alkynes to 1,2-dichlorination adducts. Aromatic, benzylic, and aliphatic C-H bonds were converted into C-Cl bonds. Detailed mechanistic investigations in the dichlorinations of alkenes were conducted on the 18VE PdIV complex. Positive solvent effects as well as kinetic measurements probing the impact of cyclohexene and chloride concentrations on the rate of alkene chlorination support a PdIV-Cl ionization in the first step. Product stereochemistry and product distributions from various alkenes also support Cl+-transfer from the pentacoordinated PdIV-intermediate LPdIVCl 3+ to olefins. 1-Hexene/3-hexene competition experiments rule out both the formation of π-complexes along the reaction coordinate as well as in situ generated Cl2 from a reductive elimination process. Instead, a ligand-mediated direct Cl+-transfer from LPd IVCl3+ to the π-system is likely to occur. Similarly, C-H bond chlorinations proceed via an electrophilic process with in situ formed LPdIVCl3+. The presence of a large excess of added Cl- slows cyclohexene chlorination while the presence of stoichiometric amounts of chloride accelerates both PdIV-Cl ionization and Cl+-transfer from LPdIVCl3 +. 1H NMR titrations, T1 relaxation time measurements, binding isotherms, and Job plot analysis point to the formation of a trifurcated Cl-...H-C bond in the NHC-ligand periphery as a supramolecular cause for the accelerated chemical events involving the metal center.
- McCall, A. Scott,Wang, Hongwang,Desper, John M.,Kraft, Stefan
-
supporting information; experimental part
p. 1832 - 1848
(2011/04/15)
-
- Regioselective synthesis of vic-halo alcohols and symmetrical or unsymmetrical vic-dihalides from epoxides using triphenylphosphine -N-halo imides
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A simple, novel, and highly regioselective cleavage of epoxides into vicinal halo alcohols and symmetrical or unsymmetrical dihalides is described using different stoichiometries of triphenylphosphine (PPh3) and N-halo succinimide (NXS) or N-halo saccharine (NXSac).
- Iranpoor, Nasser,Firouzabadi, Habib,Azadi, Roya,Ebrahimzadeh, Farzaneh
-
-
- Determination of the hydrogen-bond basicity of weak and multifunctional bases: The case of lindane (γ-hexachlorocyclohexane)
-
We made use of four methods for determining the hydrogen-bond (HB) basicity of lindane (λ-hexachlorocyclohexane): (i) experimental Fourier transform IR measurement of a sum of individual 1:1 equilibrium constants for the formation of 1:1 4-fluorophenol-lindane hydrogen-bonded complexes in CCl4; (ii) calculation of the overall HB basicity from octanol-water partition coefficients; (iii) correlation of the HB basicity of chloroalkanes with the electrostatic potentials around chlorine atoms; and (iv) correlation of the HB basicity of chloroalkanes with the computed enthalpy of their complexes with hydrogen fluoride. It is consistently found that lindane remains a weak HB base because multifunctionality cannot fully compensate for the electron-withdrawing inductive effects that chlorine atoms exert over one another. Actually, only five chlorine atoms behave as HB acceptors, one axial chlorine being deactivated by inductive effects. Stereoelectronic effects lead to the formation of three-centered hydrogen bonds. Copyright
- Ouvrard, Carole,Lucon, Maryvonne,Graton, Jerome,Berthelot, Michel,Laurence, Christian
-
-
- Use of a fluorous bridge for diffusion controlled uptake of molecular chlorine in chlorine addition to alkenes
-
Fluorous solvent was used for passive transport of molecular chlorine from one side of the U-tube to the other, where addition of chlorine to alkenes was quantitative and diffusion controlled.
- Iskra, Jernej,Stavber, Stojan,Zupan, Marko
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p. 2496 - 2497
(2007/10/03)
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- Highly efficient and selective epoxidation of alkenes by photochemical oxygenation sensitized by a ruthenium(II) porphyrin with water as both electron and oxygen donor
-
Visible light irradiation of a reaction mixture of carbonyl-coordinated tetra(2,4,6-trimethyl)-phenylporphyrinatoruthenium(II) (RuIITMP(CO)) as a photosensitizer, hexachloroplatinate(IV) as an electron acceptor, and an alkene in alkaline aqueous acetonitrile induces selective epoxidation of the alkene with high quantum yield (Φ = 0.6, selectivity = 94.4% for cyclohexene and Φ = 0.4, selectivity = 99.7% for norbornene) under degassed conditions. The oxygen atom of the epoxide was confirmed to come from a water molecule by an experiment with H218O. cis-Stilbene was converted into its epoxide, cis-stilbeneoxide, without forming trans-stilbeneoxide, trans-Stilbene, however, did not exhibit any reactivity. Under neutral conditions, an efficient buildup of the cation radical of RuIITMP(CO) was observed at the early stage of the photoreaction, while an addition of hydroxide ion caused a rapid reaction with the cation radical to promote the reaction with reversion to the starting RuIITMP(CO). A possible involvement of a higher oxidized state of Ru such as RuIV, RuV, RuVI through a dismutation of the RuIII species was excluded by an experiment with RuVITMP(O)2. Decarbonylation of the Ru complex was also proven to be invalid. A reaction mechanism involving an electron transfer from the excited triplet state of RuIITMP(CO) to hexachloroplatinate(IV) and subsequent formation of OH--coordinated RuIII species, leading to an oxo-ruthenium complex as the key intermediate of the photochemical epoxidation, was postulated.
- Funyu, Shigeaki,Isobe, Takehiko,Takagi, Shinsuke,Tryk, Donald A.,Inoue, Haruo
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p. 5734 - 5740
(2007/10/03)
-
- Studies on the interaction of phosphine selenides and their structural analogues wth dihalogens and sulfuryl chloride
-
The phosphine selenides, tris(dimethylamino)phosphine selenide, esters of selenophosphoric acid, and esters of selenophosphonic acid react with dihalogens and sulfuryl chloride to form halogenoselenophosphonium salts (≡ 3P-SeX)+X-. T
- Krawczyk, Ewa,Skowronska, Aleksandra,Michalski, Jan
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p. 4471 - 4478
(2007/10/03)
-
- Addition reactions of nitryl chloride at multiple bonds
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Published data on additio of nitryl chloride to alkenes and possible reaction mechanisms were analyzed. Reactions of nitryl chloride with alkenes differing in the ionization potentials of the double bond and in the abilities to undergo various structural rearrangements were studied. Nitryl chloride was shown to be very sensitive both to the substrate and to the reaction conditions.
- Zyk,Bondarenko,Nesterov,Zefirov
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p. 980 - 986
(2007/10/03)
-
- A new method for mixed halogenation. N-chloroamine - phosphorus bromide system as a synthetic equivalent of the mixed halogen Cl+Br-
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A new method for the mixed halogenation of alkenes has been proposed based on the reaction of olefins with N-chloroamines in the presence of phosphorus bromide or oxybromide. The plausible reaction mechanism and the results of reactions with a number of model unsaturated compounds such as cyclohexene, 1-heptene, ethyl cinnamate, norbornene and those from the bicyclo[2.2.1]heptane series are discussed. In the reactions with reactive olefins this reagent acts as a synthetic equivalent of the unknown mixed halogen [Cl+Br-] with abnormal polarity of halogen atoms. The same reactions activated by PCl3 or POCl3 result in dichlorides in yields near to quantitative.
- Zyk, Nikolai V.,Beloglazkina, Elena K.,Tyurin, Vladimir S.,Zefirov, Nikolai S.
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p. 107 - 122
(2007/10/03)
-
- Manganese-mediated Steroselective and Chemoselective trans-Dichlorination of Alkenes with Tetradecyltrimethylammonium Permangante-Trimethylchlorosilane
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An excellent reagent for the chemoselective and stereoselective trans-dichlorination of alkenes in high yield has been formulated by mixing tetradecyltrimethylammonium permanganate, a relatively stable crystalline solid with trimethylchlorosilane in methylene dichloride.
- Hazra, Braja G.,Chordia, Mahendra D.,Basu, Sourav,Bahule, Bharat B.,Pore, Vandana S.,Naskar, Dinabandhu
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p. 143 - 150
(2007/10/03)
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- Di-functionalization of alkenes using an oxidant generated from manganese(II) chloride under oxygen: Synthesis of γ-lactones
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Alkenes are oxidatively dichlorinated by stirring with manganese(II) chloride-lithium methoxide under oxygen atmosphere, followed by treatment with cone, hydrochloric acid. This di-functionalization of alkenes can be applied to the chlorolactonization of lithium 4-pentenoates.
- Hojo, Makoto,Murakami, Chikara,Ohno, Kaori,Kuboyama, Jun,Nakamura, Shin-Ya,Ito, Hajime,Hosomi, Akira
-
-
- Quaternary ammonium polychlorides as efficient reagents for chlorination of unsaturated compounds
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Chlorination of unsaturated compounds by benzyltributylammonium polychlorides results in higher yields of addition products compared to those obtained with molecular chlorine.
- Zelikman,Tyurin,Smirnov,Zyk
-
p. 1541 - 1546
(2007/10/03)
-
- Selective manganese-mediated transformations using the combination: KMnO4/Me3SiCl
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A novel manganese reagent, generated from KMnO4 and Me3SiCl, in the presence of a quaternary ammonium salt, is shown to smoothly dichlorinate alkenes, open epoxides and chemoselectively oxidise sulfides to sulfoxides.
- Marko, Istvan E.,Richardson, Paul R.,Bailey, Mark,Maguire, Anita R.,Coughlan, Niall
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p. 2339 - 2342
(2007/10/03)
-
- New applications of tungsten hexachloride (WCl6) in organic synthesis. Halo-de-hydroxylation and dihalo-de-oxo-bisubstitution reactions
-
Tungsten hexachloride (WCl6) has been used for the halo-de-hydroxylation and dihalo-de-oxo-bisubstitution reactions of benzylic alcohols, benzaldehydes, acyloins, and epoxides to their chlorides, gem-dichlorides, vic-trichlorides, and vic-dichlorides respectively.
- Firouzabadi, Habib,Shiriny, Farhad
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p. 14929 - 14936
(2007/10/03)
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- A Structurally Characterized Dichloro-manganese(IV) Complex Capable of Halogenating Alkenes
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MnIV(salpn)Cl2 regioselectively trans-halogenates alkenes in a reaction for which the Mn-containing product is also identified; this is the first Mn-based halogenating system for which the reactive and final Mn-containing products are structurally characterized.
- Law, Neil A.,Machonkin, Timothy E.,McGorman, Joel P.,Larson, Erlund J.,Kampf, Jeff W.,Pecoraro, Vincent L.
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p. 2015 - 2016
(2007/10/02)
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- Controlling the reactivity of permanganate anion. Novel, stereospecific, dichlorination of olefins
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Potassium permanganate reacts with oxalyl chloride to form a chlorine-containing manganese catalyst, of yet unknown structure, that stereospecifically trans-dichlorinates olefins.
- Marko,Richardson
-
p. 1831 - 1834
(2007/10/02)
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- Lewis acidic catalysts for olefin epoxidation by iodosylbenzene
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A ferric complex, (Et3HN) FeIII(bpb)Cl2, has been synthesized, and its structure has been determined by X-ray crystallography. This complex and its inflate derivative, (Et3HN)FeIII(bpb)(OTf)2, are found to catalyze the epoxidation of a variety of olefins by iodosylbenzene, OIPh. These reactions give little allylic oxidation of cyclohexene and stereochemical retention with cis-stilbene. Al(OTf)3, a nonredox metal salt, has also been found to catalyze the epoxidation of cyclohexene by iodosylbenzene, and the reactivity is quite similar to that of Fe(OTf)3, which, we studied previously. In addition to epoxides, other products were observed. For the reactions containing Fe(OTf)3, Al(OTf)3, or (Et3HN) FeIII(bpb)(OTf)2, cis-1,2-cyclohexanediol ditrifilate and 3-acetamidocyclohexene were found. The amide oxygen in 3-acetamidocyclohexene was derived from iodosylbenzene as verified by isotopic labeling using 18OIPh. For the reactions containing (Et3HN) FeIII(bpb)Cl2 FeCl3, or AlCl3, trans-1,2-dichlorocyclohexane and 3-chlorocyclohexene were observed. 1,4-Diiodobenzene was found in all of the reactions. The presence of these products suggests strongly that the mechanisms of these reactions are related to those occurring between soluble iodine(III)-containing compounds and olefins in the absence of any metal catalysts. A new mechanisms that accounts for all of the products is proposed which involves electrophilic attack on the olefin by the iodine(III) center in a metal-iodosylbenzene complex. The reactions of PhI(OAc)2 with norbornenecarboxylic acid or nortornene in different solvents were also investigated. The products isolated were shown to be 5-(acetyloxy)-3,3a,4,5,6,6a-hexahydro-[3β,3aα,5α,6β, 6aα]-3,6-methano-2H-cyclopenta [b] furan-2-one (1), 5-acetamido-3,3a,4,5,6,6a-hexahydro-[3β,3aα,5α,6β, 6aα]-3,6-methano-2H-cyclopenta [b] furan-2-one (2), and exo-2-acetoxy-syn-7-acetamidonorbornane (3). The structures of 1 and 3 were determined by X-ray crystallography. The formation of these products provides additional evidence for the electrophilic character of iodine(III) compounds.
- Yang, Yihui,Diederich, Fran?ois,Valentine, Joan Selverstone
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p. 7195 - 7205
(2007/10/02)
-
- Efficient Utilization of Tetrabutylammonium Bifluoride in Halofluorination Reactions
-
The halofluorination reaction of a variety of alkenes by using tetrabutylammonium bifluoride (TBABF) in the presence of N-halosuccinimide is described.This process occurs stereospecifically to afford anti addition products, and with unsymmetrical olefins a marked Markovnikov-type regioselectivity is observed.In some cases, formation of a remarkable amount of the corresponding dihalo derivatives was found, but this undesirable side reaction can be avoided by using N-iodosucciniumide (NIS) as halogenating agent.If N-bromosuccinimide (NBS) or N-chlorosuccinimide (NCS) is utilized, these dihalo compounds can be easily removed from the halofluorinated compounds by simple column chromatography on silica gel.A mechanism for this side reaction is postulated.
- Camps, F.,Chamorro, E.,Gasol, V.,Guerrero, A.
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p. 4294 - 4298
(2007/10/02)
-
- IONIC METHYLATION OF DICHLORO- AND DIBROMOALKANES
-
The dichloro and dibromo derivatives of hydrocarbons are methylated by the action of tetramethylsilane in the presence of aluminum bromide with the formation of hydrocarbons containing a quaternary carbon atom irrespective of whether the halogen atoms are at one or at different carbon atoms.
- Parnes, Z. N.,Romanova, V. S.,Vol'pin, M. E.
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p. 258 - 260
(2007/10/02)
-
- KINETIC ANALYSIS OF ALKANE POLYCHLORINATION WITH MOLECULAR CHLORINE. CHLORINE ATOM/MONOCHLORIDE GEMINATE PAIRS AND THE EFFECT OF REACTIVE 'CAGE WALLS' ON THE COMPETITION BETWEEN MONOCHLORIDE ROTATION AND CHLORINE ATOM ESCAPE.
-
The free-radical chlorination of alkanes produces polychlorides even at low conversions. These are formed by reaction of chlorine atom/monochloride (or dichloride) geminate pairs. This process has been studied in detail in various solvent systems, and a kinetic scheme has been proposed. Deviations from this scheme have been rationalized as being due to competition between monochloride rotation and reaction of the chlorine atom with reactive molecules in the 'cage walls' surrounding the chlorine atom/chloride geminate pair. Analysis of the dichloride products supports the suggestion that monochloride rotation is not completely 'free' within the lifetime of the geminate pair.
- Raner,Lusztyk,Ingold
-
p. 3519 - 3524
(2007/10/02)
-
- Gas-Phase Atomic Halogenation Reactions Using Iodine Monochloride
-
The mechanism of the photoinitiated gas-phase halogenation reactions of alkanes using iodine monochloride has been reported previously as proceeding via a radical chain process to form the corresponding alkyl chlorides.This is in marked contrast to analogous reactions with bromine-chlorine mixtures, thought to form bromine chloride, which produce alkyl bromides via a radical process.An attempt has been made to rationalize this anomaly.In this paper evidence is offered to demonstrate that under photolytic conditions, alkanes and iodine monochloride react via a radical chain process to produce initially the corresponding alkyl iodide.The reaction is shown to proceed by a chain process where the chain-carrying species is the chlorine atom.However, the reaction is complicated by further ionic reactions of the alkyl iodides, whith iodine monochloride, which produce alkyl chlorides and other polyhalogenated materials.
- Tanner, Dennis D.,Rowe, Jeffrey E.,Potter, Alan
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p. 457 - 460
(2007/10/02)
-
- CHLORINATION OF ALKENES BY MANGANESE(III) CHLORIDE SPECIES
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Several manganese(III) chloride species have been prepared in situ and used as effective chlorinating agents of alkenes.
- Donnelly, K. D.,Fristad, W. E.,Gellerman, B. J.,Peterson, J. R.,Selle, B. J.
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p. 607 - 610
(2007/10/02)
-
- MECHANISMS OF EPOXIDATIONS AND CHLORINATIONS OF HYDROCARBONS BY INORGANIC HYPOCHLORITE IN THE PRESENCE OF A PHASE-TRANSFER CATALYST.
-
Inorganic hypochlorite in the presence of a quarternary ammonium salt (phase-transfer catalyst) not only epoxidizes several arenes to arene oxides in high yields but also converts toluene to alpha -chlorotoluene, anisole to ring chlorinated anisoles, and alkenes to a complex mixture of chlorinated and oxidized products, including the epoxide. More detailed studies with this system indicate the following: (1) the high-yield conversion of toluenes to benzyl chlorides proceeds with a deuterium isotope effect of 3. 6 and a rho ** plus value of minus 1. 7: (2) p-chloroanisole is the major product from anisole and is formed in a 22-fold greater quantity than o-chloroanisole; (3) the epoxidation of cis- and trans-alkenes is stereoselective but not completely stereospecific; (4) the chlorination of saturated hydrocarbons occurs with a selectivity that is experimentally identical with that of chlorine monoxide.
- Fonouni,Krishnan,Kuhn,Hamilton
-
p. 7672 - 7676
(2007/10/02)
-
- LEAD(IV)ACETATE-METAL HALIDE REAGENTS II. A NEW METHOD FOR THE SYNTHESIS OF β-HALO CARBOXYLATES AND β-IODO ETHERS
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A new method for the synthesis of trans-β-halo carboxylates and trans-β-iodo ethers from alkenes using lead(IV)acetate-metal halide is described.KEYWORDS - lead(IV)acetate; metal halide; alkene; trans-β-halo carboxylate; trans-β-iodo ether
- Motohashi, Shigeyasu,Satomi, Masakichi,Fujimoto, Yasuo,Tatsuno, Takashi
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p. 1788 - 1791
(2007/10/02)
-
- Chlorination of Cyclohexene by Copper(II) Chloride
-
Evidence is presented which indicates that CuCl+ is the reactive species in the chlorination of cyclohexene by copper(II) chloride in acetonitrile.The reaction is retarded by an excess of chloride ion and by copper(I) salts, and accelerated by aluminium trichloride.A kinetic scheme which accounts for these observations is suggested.
- Gamlen, Philip H.,Henty, Michael S.,Roberts, Hugh L.
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p. 1373 - 1376
(2007/10/02)
-
- EPOXIDATION WITH THE H2O2/VILSMEIER REAGENT SYSTEM
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Alkenes 1 a-d interact at -80 deg C in 15 min. with the Vilsmeier reagent I (Me2N=CHCl)(+) PO2Cl2(-) in presence of 30percent H2O2 to yield the corresponding epoxides 3 a-d.The reaction could involve the formation of the highly reactive hydroperoxymethylenedimethylammonium salt (Me2N=CHOOH)(+) PO2Cl2(-) II.
- Dulcere, Jean-Pierre,Rodriguez, Jean
-
p. 1887 - 1888
(2007/10/02)
-
- Peroxide-induced α-Elimination of Organic Halides from Organotellurium(IV) Halides
-
Treatment of organotellurium(IV) halides with t-butyl hydroperoxide in 1,4-dioxan, acetic acid, or acetonitrile affords the corresponding organic halides in good to moderate yields presumably as the result of a 1,2-halogen shift.
- Uemura, Sakae,Fukuzawa, Shin-ichi
-
p. 1033 - 1034
(2007/10/02)
-
- Chlorination of Organic Compounds by Means of Polymer-supported Chlorine
-
Chlorination of organic compounds is achieved, under mild conditions, using chlorine incorporated into an anion-exchange resin.
- Bongini, Alessandro,Cainelli, Gianfranco,Contento, Michele,Manescalchi, Francesco
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p. 1278 - 1279
(2007/10/02)
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- Three-Component Reactions. VIII. Chlorination of Olefines in N-Methylpyrrolidone
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The chlorination of cyclohexene, styrene and 1-dodecene in NMP gives immonium-chlorides 5 reacting with water to β-chloralkyl-γ-N-methylaminobutyrat-hydrochlorides.With cyclohexene the reaction proceeds stereospecifically as trans-addition.From styrene there is only formed the Markovnikov product, and from dodecene a mixture of isomeres is obtained containing about 30percent of the anti-Markovnikov product.
- Beger, J.,Jacobi, R.,Storch, A.,Ullmann, M.
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p. 394 - 400
(2007/10/02)
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