96-11-7Relevant articles and documents
BROMINATED FLAME RETARDANTS AND POLYURETHANES CONTAINING THE SAME
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Paragraph 0122; 0123, (2020/07/15)
The disclosure includes brominated alkenyl alcohols, their use as a flame retardant in polyurethane and polyurethane foams, and polyurethanes containing the brominated alkenyl alcohols. Compositions, methods, and processes are disclosed. The brominated alkenyl alcohols used as flame retardants in polyurethanes can be generally described by Formula (I), the scope of which is disclosed herein.
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
Nokhbeh, Seyed Reza,Gholizadeh, Mostafa,Salimi, Alireza,Sparkes, Hazel A.
, p. 542 - 554 (2019/06/18)
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.
A novel route for the synthesis of alkanes from glycerol in a two step process using a Pd/SBA-15 catalyst
Udayakumar,Pandurangan
, p. 78719 - 78727 (2015/10/05)
Glycerol is produced as a valuable by-product in the transesterification of fatty acids, but it cannot be used directly as a fuel additive. In this study, we developed a systematic conversion for glycerol, which proceeds via synthesizing the key intermediate, 1,2,3-tribromopropane and using the Suzuki coupling reaction to introduce the alkyl group. A series of Pd/SBA-15 catalysts with different wt% of Pd (10%, 15% and 20%) was prepared by a one step sol-gel method. The structure and composition of the catalysts were characterized by X-ray diffraction analysis (XRD), N2 adsorption-desorption isotherms, transmission electron microscopy (TEM) and inductively coupled plasma optical emission spectrometry (ICP-OES). The metallic state of dispersed palladium in SBA-15 is confirmed with X-ray photoelectron spectroscopy (XPS). Pd/SBA-15 with a Pd loading of 20 wt% shows good catalytic activity at 90 °C with methylboronic acid, allowing the complete conversion of 1,2,3-tribromopropane and 64% selectivity of 3-methylpentane. The optimized catalysts were also employed in coupling reactions between various alkylhalides and methylboronic acid, which obtained the desired product with an excellent selectivity. The catalyst can be successfully recycled five times. After the first cycle, we observed a drop in activity with 20% Pd/SBA-15, which was due to the leaching of palladium but in the later cycles, there was no significant decrease in activity.
Ynamide Carbopalladation: A Flexible Route to Mono-, Bi- and Tricyclic Azacycles
Campbell, Craig D.,Greenaway, Rebecca L.,Holton, Oliver T.,Walker, P. Ross,Chapman, Helen A.,Russell, C. Adam,Carr, Greg,Thomson, Amber L.,Anderson, Edward A.
supporting information, p. 12627 - 12639 (2015/09/01)
Bromoenynamides represent precursors to a diversity of azacycles by a cascade sequence of carbopalladation followed by cross-coupling/electrocyclization, or reduction processes. Full details of our investigations into intramolecular ynamide carbopalladation are disclosed, which include the first examples of carbopalladation/cross-coupling reactions using potassium organotrifluoroborate salts; and an understanding of factors influencing the success of these processes, including ring size, and the nature of the coupling partner. Additional mechanistic observations are reported, such as the isolation of triene intermediates for electrocyclization. A variety of hetero-Diels-Alder reactions using the product heterocycles are also described, which provide insight into Diels-Alder regioselectivity.
Copper-catalyzed allylation of a,a-difluoro-substituted organozinc reagents
Zemtsov, Artem A.,Kondratyev, Nikolay S.,Levin, Vitalij V.,Struchkova, Marina I.,Dilman, Alexander D.
, p. 818 - 822 (2014/04/03)
A method for the coupling of organozinc reagents, difluorocarbene, and allylic electrophiles is described. The reaction involves insertion of difluorocarbene into the carbon-zinc bond followed by copper-catalyzed allylic substitution.
Bis(allyl)aluminum cation, tris(allyl)aluminum, and tetrakis(allyl) aluminate: Synthesis, characterization, and reactivity
Lichtenberg, Crispin,Robert, Dominique,Spaniol, Thomas P.,Okuda, Jun
experimental part, p. 5714 - 5721 (2011/02/17)
Cationic, neutral, and anionic aluminum allyl compounds were synthesized, and their reactivity toward electrophiles was studied. The THF adduct of the previously elusive tris(allyl)aluminum, [Al(η1-C 3H5)3(THF)] (1), was isolated as an oil. Protonolysis of one allyl ligand in 1 using [NEt3H][BPh4] gave the cationic bis(allyl)aluminum, a fragment of the crystalline [Al(η1-C3H5)2(THF) 3-n]+[BPh4]-·(n+1)THF (n = 0, 1) (2). Single-crystal X-ray diffraction of [Al(η1-C 3H5)2(THF)2]+[BPh 4]- (2a) revealed a tetrahedral aluminum center, while [Al(η1-C3H5)2(THF) 3]+[BPh4]- (2b) contains a trigonal-bipyramidal aluminum center with both allyl ligands in the equatorial plane. The tetrakis(allyl)aluminate K+[Al(η1-C 3H5)4]- (3) was also synthesized from the reaction of 1 with K(C3H5). Reactions of the allyl compounds 1-3 with (i) benzophenone, (ii) allyl halides C 3H5X (X = Cl, Br, I), and (iii) halogen X2 (X = Br, I) showed considerable difference with respect to the ionic charge of the aluminum allyl.
Dioxane dibromide-mediated solvent-free synthesis of vicinal dibromides
Chaudhuri, Subrata Kumar,Roy, Sanchita,Saha, Manabendra,Bhar, Sanjay
, p. 271 - 274 (2007/10/03)
Structurally varied vicinal dibromides have been synthesized in high yield and good purity through highly stereoselective anti-addition of bromine across the olefinic linkages using dioxane dibromide (DD) under solvent-free conditions. Copyright Taylor & Francis Group, LLC.
NaIO4-Mediated Selective Oxidative Halogenation of Alkenes and Aromatics Using Alkali Metal Halides
Dewkar, Gajanan K.,Narina, Srinivasarao V.,Sudalai, Arumugam
, p. 4501 - 4504 (2007/10/03)
(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.
Perfluorohexane as a novel reaction medium for bromination reactions
Pereira,Savage,Simpson
, p. 1023 - 1026 (2007/10/02)
Perfluorohexane is shown to be a good alternative to carbon tetrachloride as a non-toxic, non-ozone-depleting, inert reaction medium for bromination reactions. Yields of brominated products were nearly quantitative and the reaction work-up was easier.
REACTION OF ORGANIC COMPOUNDS WITH SF4-HF-HALOGENATING SYSTEM VII. REACTIONS OF OLEFINS WITH THE SF4-HF-Cl2(Br2) SYSTEM
Kunshenko, B. V.,Mokhamed, Nagib Mukhtar,Omarov, V. O.,Muratov, N. N.,Yagupol'skii, L. M.
, p. 511 - 518 (2007/10/02)
Under the influence of the SF4-HF-Cl2(Br2) system halogen-containing olefins undergo conjugate halogenofluorination.It was shown for the case of (Z)- and (E)- 1,2-dichloroethenes that these reactions take place anti-stereospecifically through the formation of the bromonium ions.The accumulation of chlorine atoms in the olefin molecule hinders electrophilic addition of stoichiometric equivalents of ClF and BrF at the double bond.The SF4-HF-Br2 system is an effective agent for substitutive fluorination of organic compounds containing bromine.Only the bromine atoms situated at the secondary carbon atom are substituted by fluorine.
