- Crystal structure, characterization, Hirshfeld surface analysis and DFT studies of two [propane 3-bromo-1-(triphenyl phosphonium)] cations containing bromide (I) and tribromide (II) anions: The anion (II) as a new brominating agent for unsaturated compounds
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In this study, propane 3-bromo-1- (triphenyl phosphonium) bromide, I, and propane 3-bromo-1- (triphenyl phosphonium) tribromide, II, (II as a new brominating agent) were synthesized and characterized by 1H NMR, 13C NMR, 31P NMR, FT-IR, spectroscopy, Thermogravimetric Analysis, Differential thermal analysis, Differential scanning calorimetry and single crystal X-ray analysis. Density functional theory calculations (energy, structural optimization and frequencies, Natural Bond Orbital, absorption energy and binding energy) were performed by using B3LYP/6-311 G++ (d, p) level of theory. Hirshfeld surface analysis and fingerprint plots were utilized to investigate the role of bromide and tribromide anions on the crystal packing structures of title compounds. The results revealed that the change of accompanying anionic moiety can affect the directional interactions of C-H?Br hydrogen bonds between anionic and cationic units in which the H?Br with a proportion of 53.8% and 40.9% have the major contribution in the stabilization of crystal structures of I and II, respectively. Furthermore, the thermal stability of new brominating agent II with tribromide anion was compared with compound I with bromide anion. Nontoxicity, short reaction time, thermal stability, simple working up and high yield are some of the advantages of these salts.
- Nokhbeh, Seyed Reza,Gholizadeh, Mostafa,Salimi, Alireza,Sparkes, Hazel A.
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p. 542 - 554
(2019/06/18)
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- One-Pot Strategy for Thiazoline Synthesis from Alkenes and Thioamides
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A convenient synthesis of a privileged pharmaceutical motif, thiazoline is accomplished. This reaction utilizes simple and readily available alkene and thioamide substrates in an intermolecular fashion via a simple one-pot procedure. A wide range of functional groups is tolerated, and the thiazoline product has been further utilized for the synthesis of the corresponding β-aminothiol and thiazole from routine hydrolysis and oxidation protocols.
- Alom, Nur-E,Wu, Fan,Li, Wei
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supporting information
p. 930 - 933
(2017/02/26)
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- Selective bromochlorination of a homoallylic alcohol for the total synthesis of (-)-Anverene
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The scope of a recently reported method for the catalytic enantioselective bromochlorination of allylic alcohols is expanded to include a specific homoallylic alcohol. Critical factors for optimization of this reaction are highlighted. The utility of the
- Seidl, Frederick J.,Burns, Noah Z.
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supporting information
p. 1361 - 1365
(2016/08/02)
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- Bromination of olefins with HBr and DMSO
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A simple and inexpensive methodology is reported for the conversion of alkenes to 1,2-dibromo alkanes via oxidative bromination using HBr paired with dimethyl sulfoxide, which serves as the oxidant as well as cosolvent. The substrate scope includes 21 olefins brominated in good to excellent yields. Three of six styrene derivatives yielded bromohydrins under the reaction conditions.
- Karki, Megha,Magolan, Jakob
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p. 3701 - 3707
(2015/04/22)
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- Bromination of alkenols with the H2O2 - LiBr - CeIII and H2O2 - LiBr - CeIV systems
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Reactions of alkenols with H2O2 - LiBr - Ce(NO 3)3·6H2O or H2O2 - LiBr - Ce(NH4)2(NO3)6 system led to bromination of the double bond to yield vicinal dibromoalkanols. The reaction proceeded highly selectively, no oxidation of the hydroxyl group virtually occurred.
- Nikishin,Sokova,Kapustina
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p. 459 - 463
(2013/07/05)
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- A combination of in vivo selection and cell sorting for the identification of enantioselective biocatalysts
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The "carrot and stick" principle could be combined with cell sorting to enable the selection of enantioselective esterase variants from a mutant library. Hence, the enormous diversity generated in directed evolution experiments is now easily accessible by this high-throughput system. In line with the principle, the hydrolysis of 1 glycerin supports cell growth, whereas the hydrolysis of 2 leads to cell death. Copyright
- Fernandez-Alvaro, Elena,Snajdrova, Radka,Jochens, Helge,Davids, Timo,Boettcher, Dominique,Bornscheuer, Uwe T.
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supporting information; experimental part
p. 8584 - 8587
(2011/11/07)
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- Monobromoborane-dimethyl sulfide - A highly promising reagent for the regio- and chemoselective brominative cleavage of terminal epoxides into vicinal bromohydrins
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Monobromoborane?dimethyl sulfide (BH2Br?SMe2) is a highly regio- and chemoselective reagent useful for the brominative cleavage of the epoxy moiety into bromohydrins in the presence of alkenes, alkynes, ethers, acetals, ketals, and acetonides at 0°C, besides being an excellent hydroborating reagent. Several reactive functional groups, such as chloride, ketones, esters, nitriles, nitros, and thioethers, have been accommodated during such transformations. Although the reduction of acetophenone was completely suppressed at ?25°C, 4-chlorobenzaldehyde still underwent 12?13% reduction of an aldehydic group. CSIRO 2007.
- Roy, Chandra D.,Brown, Herbert C.
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p. 139 - 145
(2008/02/11)
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- Dimethoxyboron bromide - A new, efficient, regio- and chemoselective reagent for the conversion of terminal epoxides into bromohydrins
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Dimethoxyboron bromide, (MeO)2BBr, easily prepared in excellent yield from boron tribromide and trimethyl borate, is a new, efficient, regio- and chemoselective reagent useful for the halogenative cleavage of compounds containing epoxy groups into vicinal bromohydrins in the presence of ether, acetal, ketal, N-oxide, and sulfoxide groups, at low temperatures (-78°C).
- Roy, Chandra D.,Brown, Herbert C.
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p. 639 - 641
(2007/10/03)
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- Poly(vinylpyrrolidone)-bromine complex; a mild and efficient reagent for selective bromination of alkenes and oxidation of alcohols
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Poly(vinylpyrrolidone)-bromine complex (PVP-Br2) is easily prepared and used as a mild and convenient reagent for selective bromination of alkenes and at the position α-hydrogen of active carbonyl compounds. Selective oxidation of benzylic alcohols in the presence of aliphatic alcohols were also achieved at room temperature.
- Lakouraj, Moslem Mansour,Tajbakhsh, Mahmood,Mokhtary, Masoud
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p. 481 - 483
(2007/10/03)
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- NaIO4-Mediated Selective Oxidative Halogenation of Alkenes and Aromatics Using Alkali Metal Halides
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(Equation presented) NaIO4 oxidizes alkali metal halides efficiently in aqueous medium to halogenate alkenes and aromatics and produce the corresponding halo derivatives in excellent regio and stereoselectivity. The system also demonstrates the asymmetric version of bromo hydroxylation using β-cyclodextrin complexes, resulting in moderate ee.
- Dewkar, Gajanan K.,Narina, Srinivasarao V.,Sudalai, Arumugam
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p. 4501 - 4504
(2007/10/03)
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- A tandem enzyme reaction to produce optically active halohydrins, epoxides and diols
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The recombinant halohydrin dehalogenase from Agrobacterium radiobacter AD1 was used to obtain enantiomerically pure halohydrins and epoxides by kinetic resolution. By adding an excess of the recombinant epoxide hydrolase from the same organism the reversible conversion was drawn to completion. Halohydrins such as (S)-2,3-dichloro-1-propanol (E>100) and (S)-2-chloro-1-phenylethanol (E=73) were obtained with an enantiomeric excess of higher than 99%. This is a novel biocatalytic route for obtaining enantiomerically pure aromatic halohydrins and epoxides.
- Lutje Spelberg, Jeffrey H.,Van Hylckama Vlieg, Johan E. T.,Bosma, Tjibbe,Kellogg, Richard M.,Janssen, Dick B.
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p. 2863 - 2870
(2007/10/03)
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- An environmentally benign synthesis of organic ammonium tribromides (OATB) and bromination of selected organic substrates by tetrabutylammonium tribromide (TBATB)
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Stable crystalline organic ammonium tribromides (OATB), like Me4NBr3, Et4NBr3, Bu4NBr3, cetyltrimethylammonium tribromide, PyHBr3, can be readily synthesised from the reaction of the corresponding bromides with V2O5 and aqueous H2O2. Typically, TBATB, Bu4NBr3, brominates a variety of organic substrates rather easily under mild conditions. An activated aromatic ring is selectively brominated in the presence of an olefinic double bond.
- Chaudhuri, Mihir K.,Khan, Abu T.,Patel, Bhisma K.,Dey, Deepa,Kharmawophlang, Wancydora,Lakshmiprabha,Mandal, Gagan C.
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p. 8163 - 8166
(2007/10/03)
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- A simple preparation of N-vinyl derivatives of DNA nucleobases
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1-Vinylpyrimidines and 9-vinylpurines have been prepared via selective alkylation of the heterocyclic ring with 1,2-dibromoethane (or 1,2- dibromopropanol) followed by dehydrobromination with sodium ethoxide in ethanol/DMF.
- Ciapetti, Paola,Taddei, Maurizio
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p. 11305 - 11310
(2007/10/03)
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- Pd(0)-based synthetic approaches to 1,1-disubstituted-3,4-dimethylenecyclopentanes as intermediates in the preparation of a,a-disubstituted amino acid derivatives possessing indane and diazaindane skeletons
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A comparison is established between ethyl nitroacetate and ethyl N(diphenylmelhylene)glycinate as anionic glycine equivalents for the preparation of bicyclic or tricyclic a.adisubstituted amino acids. Palladiummediated approaches to 1.1disubstituted-3,4-di methylene cyclopentanes are presented (intramolecular reductive coupling of 2.6-dibromol.6dienes and cycloisomerization of 1.6enynes). Springer-Verlag Iberica 1997.
- Loepez, Anna,Moreno-Manas, Marcial,Pleixats, Roser,Roglans, Anna
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p. 355 - 362
(2007/10/03)
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- Synthesis of Dibromohydrins from Glycerol by Using an Ion Exchange Resin as Catalyst
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Bromination of glycerol by 48percent hydrobromic acid in the presence of an acid ion exchange resin (C264 or A19) led to the formation of a mixture of 1,3- and 2,3-dibromohydrins in a yield of around 70percent.The side products were essentially brominated polyglycerols.
- Bouillaud, Alain,Dargelos, Marianne,Borredon, Marie-Elisabeth
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p. 2123 - 2128
(2007/10/02)
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- BROMINATION OF ALKENES AND ALKYNES WITH BIS(DIMETHYLACETAMIDO)HYDROGEN TRIBROMIDE
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The brominating characteristics of bis(dimethylacetamido)hydrogen tribromide were studied in the bromination of a series of alkenes and alkynes. The yields of the bromination products are the same as with molecular bromine and are noticeably higher in the case of the most reactive alkenes.
- Rodygin, M. Yu.,Mikhailov, V. A.,Zubritskii, M. Yu.,Savelova, V. A.
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p. 359 - 363
(2007/10/02)
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- STUDY OF THE BROMINATION OF SOME ORGANIC COMPOUNDS IN WATER-ACETONITRILE MIXTURES BY THE ROTATING RING-DISC ELECTRODE TECHNIQUE
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A platinum ring - platinum disc rotating electrode was employed to investigate the kinetics for the bromination of some organic compounds (n-hexene, styrene, allyl alcohol and anisol) by bromine, generated with controlled current at the disc.The experiments were performed in a mixed solvent which contained 90 vol.percent acetonitrile and 10 vol.percent water.
- Malyszko, J.,Niewiadomski, T.
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p. 185 - 191
(2007/10/02)
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- Degradation of 2,3-Dichloro-1-propanol by a Pseudomonas sp.
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A bacterium that assimilates 2,3-dichloro-1-propanol was isolated from soil by enrichment culture.The strain was identified as Pseudomonas sp. by the taxonomic studies.The strain converted 2,3-dichloro-1-propanol to 3-chloro 1,2-propanediol, releasing chloride ions.The conversion was stereospecific because the residual 2,3-dichloro-1-propanol and formed 3-chloro-1,2-propanediol gave optical rotation.The resting cells converted various halohydrins to the dehalogenated alcohols, and cell-free extracts had strong epoxyhydrolase activity.These results indicated that the strain assimilated 2,3-dichloro-1-propanol via 3-chloro-1,2-propanediol, glycidol and glycerol.The possibility to manufacture optically active 2,3-dichloro-1-propanol is discussed.
- Kasai, Naoya,Tsujimura, Kazuya,Unoura, Kinya,Suzuki, Toshio
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p. 3185 - 3190
(2007/10/02)
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- HALONIUM ION-INDUCED BIOSYNTHESIS OF CHLORINATED MARINE METABOLITES
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Bromoperoxidases do not directly oxidize the chloride ion; nevertheless, in the presence of bromide ions, chloride ions and hydrogen peroxide, bromoperoxidases react with alkenes and alkynes to produce bromochloro-derivatives.This same reaction is catalysed when seawater is the source of chloride and bromide ions.This suggests that bromonium ion-induced biosynthesis of chlorinated metabolites occurs in marine environments.The role of iodonium ions in the biosynthesis of chlorinated metabolites is also discussed.Key Word Index - Coralina sp.; Rhodophyta; biological halogenation; bromoperoxidase; enzymatic bromochlorination; marine chlorination; role of bromonium ions and iodonium ions; seawater.
- Geigert, John,Neidleman, Saul L.,Witt, Susanne K. de,Dalietos, Demetrios J.
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p. 287 - 290
(2007/10/02)
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- Preparation of (+)- and (-)-2,3-Dibromo-1-propanols
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The enantiomers of 2,3-dibromo-1-propanol were obtained by diazotization of the diastereomeric d-tartrate salts of 2,3-dibromopropylamine.The products of the reaction contained approximately 13percent of the secondary alcohol 1,3-dibromo-2-propanol which was separated by either column chromatography on silica gel or preparative GLC to obtain the primary alcohols (+)-2,3-dibromo-1-propanol (26D +13.8 deg) and (-)-2,3-dibromo-1-propanol (24D -12.8 deg).NMR and EI mass spectra of the primary and secondary dibromopropanols clearly distinguished the structuralisomers from one another.The optical isomers will be used to examine possible stereoselective differences in mutagenic potency, since 2,3-dibromo-1-propanol is a mutagenic metabolite of the potent mutagen and carcinogen tris(2,3-dibromopropyl) phosphate.
- Huitric, Alain C.,Gordon, W. Perry,Nelson, Sidney D.
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p. 474 - 475
(2007/10/02)
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