Category: 594-81-0

Park, P. J. D. published the artcileSpectroscopic and acoustic studies on the rotational isomerism in 2,3-dibromo-2,3-dimethylbutane, Name: 2,3-Dibromo-2,3-dimethylbutane, the publication is Journal of the Chemical Society [Section] A: Inorganic, Physical, Theoretical (1968), 2064-7, database is CAplus.

The vibrational spectra of 2,3-dibromo-2,3-dimethylbutane (I) were measured in various phases. In the liquid phase, I exists as an equilibrium mixture of rotational isomers. A proposed frequency assignment of the gaucheand trans-isomers is given. A value of 6-7.5 kcal./mole was estimated for the energy of activation for the gauche → trans isomerization from acoustic measurements at ∼50°.

Journal of the Chemical Society [Section] A: Inorganic, Physical, Theoretical published new progress about 594-81-0. 594-81-0 belongs to bromides-buliding-blocks, auxiliary class Bromide,Aliphatic hydrocarbon chain, name is 2,3-Dibromo-2,3-dimethylbutane, and the molecular formula is C6H12Br2, Name: 2,3-Dibromo-2,3-dimethylbutane.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Park, P. J. D. published the artcileThe infrared spectra of pressed-disk samples in relation to molecular structure in 2,3-dibromo-2,3-dimethylbutane, Computed Properties of 594-81-0, the publication is Chemical Communications (London) (1966), 557-8, database is CAplus.

The ir spectra of 2,3-dibromo-2,3-dimethylbutane (I) were determined for mull, crystal, dilute solution, liquid at high temperatures, and mull pressed-disk samples in order to clarify discrepancies between earlier spectroscopic and dipole-moment studies. The spectra of solid mull and crystal samples were in agreement with those reported previously. When the ir and Raman spectra of the crystal form were compared, the rule of mutual exclusion was found to apply. The crystal was entirely the trans form with mol. sym. C_2h. When the ir spectra of liquid I and dilute solutions were examined, addnl. weak absorption bands unreported previously were observed at 1283, 1263, 1190, 1055, 1020, 1005, 947, 925, 682, and 490 cm.^-1 These were assigned to the gauche isomer. Addnl. bands appeared also in the pressed-disk spectrum of I, corresponding almost exactly in frequency to those bands assigned to the gauche compound During the preparation of the pressed-disk samples, internal rotation was concluded to have occurred, with some mols. changing from the trans to the gauche form.

Chemical Communications (London) published new progress about 594-81-0. 594-81-0 belongs to bromides-buliding-blocks, auxiliary class Bromide,Aliphatic hydrocarbon chain, name is 2,3-Dibromo-2,3-dimethylbutane, and the molecular formula is C6H12Br2, Computed Properties of 594-81-0.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Kohlrausch, K. W. F. published the artcileRaman effect. CXVIII. 10. Dihaloethanes, Category: bromides-buliding-blocks, the publication is Z. physik. Chem. (1940), 55-65, database is CAplus.

New data, including some polarization measurements, have been obtained for 1,2-dichloro-, dibromo-, chlorobromo- and chloroiodoethane. The results are compared with previous vibrational Raman spectra on these compounds The presence of both cis and trans forms is indicated by the chain and CH-vibrational frequencies.

Z. physik. Chem. published new progress about 594-81-0. 594-81-0 belongs to bromides-buliding-blocks, auxiliary class Bromide,Aliphatic hydrocarbon chain, name is 2,3-Dibromo-2,3-dimethylbutane, and the molecular formula is C6H12Br2, Category: bromides-buliding-blocks.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Hueckel, Walter published the artcileRates of cleavage and dipole moments of 1,2-dibromides, Quality Control of 594-81-0, the publication is Justus Liebigs Annalen der Chemie (1963), 17-30, database is CAplus.

cf. following abstract The rates of Br cleavage from 1,2-dibromocyclohexane, 1,2- (I), 2,3- (II), and 9,10-dibromo-trans-decalin (III), 2,3-dibromo-cis-decalin cleavage from 1,2-dibromocyclohexane, 1,2-, 2,3-, and 9,10-dibromo-trans-decalin (I), (II), and (III), 2,3-dibromo-cis-decalin (IV), 1,2-dibromo-1-methylcyclohexane, Me₂CBrCHBrMe, 1,2-dibromo-1,2-dimethylcyclohexane, and Me₂CBrCBrMe₂ by iodine-absolute MeOH were measured at 15-75° and related to the dipole moment. The rate depended on the type of CBr bond (secondary-secondary < secondary-tertiary < tertiary-tertiary; the rate constants of each group differed from those of the previous group by a factor of approx. 10². The conformation as derived from the dipole moment appeared of secondary significance. Quant., the differences in rate constant were too small to verify the 4-center principle for the transition state (Rice and Teller, CA 32, 7405⁶). Suitable, simple, isomeric trans-dibromides with the same C skeleton and fixed axial-axial, axial-equatorial, and equatorial-equatorial positions could not be obtained. The reaction product of 200 g. benzoquinone and 75 l. H₂C:CHCH:CH₂ was reduced without isolation, with 350 g. Zn dust in 900 ml. glacial HOAc to give 215 g. octalindione, m. 100-2° (1:1 petr. ether-C₆H₆), of which 60 g. treated with 70 g. KOH and 60 ml. 80% N₂H₄.H₂O in 500 ml. HOCH₂CH₂OH gave 33.5 g. Octalin, b. 67-73°, n²⁰_D 1.4847, n²⁵_D 1.4824. Of this 43 g., distilled through a spinning band column, collecting 2 g. fractions, gave: fractions 2-12, pure trans-Δ²-octalin, b₁₀ 67.5-8.0° (redistilled over Na, d₂₀ 0.89151, n²⁰_D 1.4815, n²⁵_D 1.4792, MR_D 43.52, m. -3.5°), and fractions 18-21, pure cis-Δ²-octalin, b₁₀ 73° (redistilled over Na, d₂₀ 0.92152, n²⁰_D 1.4936, MR_D 43.01). The appropriate octalin (10 g.) in 50 ml. anhydrous CHCl₃ was treated with 12 g. Br in 50 ml. CHCl₃ under anhydrous conditions, and the reaction mixture washed with NaHSO₃ and H₂O, dried, and evaporated to give a residue which was crystallized from EtOH and recrystallized to give the following decalins: II, m. 84.5-5.5° (EtOH or Me₂CO); I, m. 46° (EtOH, petr. ether, or Me₂CO); 2,3-dibromo-trans-decalin, m. 61° (30-50° petr. ether); trans-1,2-dibromo-cis-decalin, m. 37° (EtOH). 2,3(a,a)-Dibromo-trans-decalin heated 20 hrs. at 120° gave an equilibrium mixture which was separated by chromatography on Kieselgel eluting with petr. ether (b. 50-6°) to give starting material and 2,3(e,e)-dibromo-trans-decalin, m. 60°, which was reduced with Zn dust in EtOH at 65° to give pure trans-Δ²-octalin.

Justus Liebigs Annalen der Chemie published new progress about 594-81-0. 594-81-0 belongs to bromides-buliding-blocks, auxiliary class Bromide,Aliphatic hydrocarbon chain, name is 2,3-Dibromo-2,3-dimethylbutane, and the molecular formula is C6H12Br2, Quality Control of 594-81-0.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Vereshchagin, A. N. published the artcileAnisotropy of polarizability and dipole moments of some 1,2-dibromoethane derivatives, Quality Control of 594-81-0, the publication is Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya (1973), 163-5, database is CAplus.

Kerr constants and dipole moments of BrRR1CCR2R3Br (I, R-R3 = H, Me, Ph) were reported. The trans conformers of such compounds had effective dipole moments that could not be described by the simple moment-additive scheme. The Me-substituted I in solution were mainly in transform whereas Ph shifted the conformational equilibriumsubstantially by destabilizing the trans location of the 2 Br atoms probably by gauche interaction of Ph and Br components. This interaction was ∼1.2 cal/mole.

Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya published new progress about 594-81-0. 594-81-0 belongs to bromides-buliding-blocks, auxiliary class Bromide,Aliphatic hydrocarbon chain, name is 2,3-Dibromo-2,3-dimethylbutane, and the molecular formula is C38H24F4O4P2, Quality Control of 594-81-0.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Kahovec, L. published the artcileRaman effect. CXVII. Rotation isomerism. 9. Polyhaloalkanes, Recommanded Product: 2,3-Dibromo-2,3-dimethylbutane, the publication is Z. physik. Chem. (1940), 48-54, database is CAplus.

Results were obtained for Me₂CX₂, X = Br, I; MeCHXCH₂X, X = Cl, Br; ICH₂CH₂CH₂I; MeCHI₂; BrCH₂CHBr₂; MeCH₂CHMe₂; XMe₂CCMe₂X, X = Cl, Br. Increase in the number of frequencies around 800 cm.^-1 in the series of dihalopropanes and for the CX valence vibrations in the trihaloethanes is attributed to rotation isomerism.

Z. physik. Chem. published new progress about 594-81-0. 594-81-0 belongs to bromides-buliding-blocks, auxiliary class Bromide,Aliphatic hydrocarbon chain, name is 2,3-Dibromo-2,3-dimethylbutane, and the molecular formula is C6H12Br2, Recommanded Product: 2,3-Dibromo-2,3-dimethylbutane.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Wittig, Georg published the artcileNewer syntheses of cyclopolyenes. III. 5,8-diphenyl-1,2,3,4-dibenzocycloöctatetraene, Product Details of C6H12Br2, the publication is Justus Liebigs Annalen der Chemie (1956), 93-104, database is CAplus.

cf. C.A. 50, 8678f; preceding abstract To 12.4 millimoles LiMe in 25 cc. Et₂O under N were added very gradually 6.2 millimoles finely powd. (o-BzC₆H₄)₂ (I), m. 166-7°, yielding 2 g. mixture (II) of diastereoisomers, C₂₈H₂₆O₂, m. 149-77°, from which was isolated by repeated crystallization 39% [2-PhCMe(OH)C₆H₄]₂, m. 199.5-200° (from MeOH). II (1.1 g.) in 22 g. warm glacial AcOH and a few drops concentrated HCl was boiled 10 min., giving 94-6% 5-methyl-5,7-diphenyl-1,2,3,4-dibenzo-1,3,6-cycloheptatriene (III), m. 209-10° (from AcOEt). III (1 g.) in 30 cc. glacial AcOH was refluxed 6 hrs. with 5 cc. concentrated HI and 0.2 g. red P, poured into 70 cc. H₂O, filtered, extracted with AcOEt, refiltered, and the filtrate evaporated, giving 37% 5-methyl-5,7-diphenyl-1,2,3,4-dibenzo-1,3-cycloheptadiene, m. 127.5-29° (from MeOH), 1 g. of which in 15 cc. CCl₄ was boiled 0.5 hr. with 0.5 g. N-bromosuccinimide (freeing HBr), giving 88% III. I (13.5 g.) was shaken 3 days with a suspension of Ph₃P:CH₂ in 200 cc. Et₂O (prepared from 0.1 mole Ph₃PMeBr and 0.12 mole PhLi), centrifuged and the supernatant liquor treated with Et₂O and recentrifuged, and treated with H₂O yielding 19.2 g. insoluble Ph₃PO and from the Et₂O mother liquors (after washing with H₂O) 11.4 g. [o-PhC(:CH₂)C₆H₄]₂ (IV), m. 100-1° (from EtOH). IV in AcOH heated with a few drops HCl gave III. IV (1 g.) in Me₂CO, oxidized 12 hrs. at 40° with 5.4 millimoles KMnO₄, heated with MeOH, and filtered gave 71% I. IV (1 g.) in 20 cc. absolute Et₂O was shaken 8 hrs. under N with 1 g. Na wire followed by decantation, and titration with 0.25N MeOH (in Et₂O) to a colorless endpoint, washing with H₂O, and evaporation of the Et₂O gave 23% Va or Vb, rectangles, m. 177-8° (from Me₂CO). Inasmuch as the ultraviolet absorption spectrum of Va or Vb (in cyclohexane) resembles those of 9,10-dihydrophenanthrene and bisdiphenylenecyclobutane, structure Va is the more probable one. The spectrum of Vb would be expected to be similar to that of (2-MeC₆H₄)₂. When 1 g. IV in 30 cc. Et₂O was shaken 3 days with 1 g. Na, the reaction was more extensive (about 75% as indicated by the MeOH titration); a diastereoisomeric mixture (VI) (52.5%), m. 196-218° (from Me₂CO), was isolated; this when chromatographed on Al₂O₃ using cyclohexane-CCl₄ as developer gave 9.4% 5,8-diphenyl-1,2,3,4-dibenzo-1,3-cycloöctadiene (VII), m. 240-40.5°. Va (0.1 g.) in 15 cc. (CH₂OMe)₂ shaken 2 hrs. with 0.5 g. Na showed that about 93% had reacted and 71% of the calculated amount of VI, m. 194-205°, was isolated. The 5,8-di-Na complex (VIII) corresponding to VII was prepared under fully described conditions, from 7.3 millimoles IV and 1 g. Na; VIII was added to 8.4 millimoles (Me₂CBr)₂, m. 168-70°, in Et₂O. The decolorized mixture was washed with H₂O, freed from Et₂O and (Me₂C:)₂, taken up in cyclohexane, chromatographed on Al₂O₃ and eluted, with CCl₄, giving 30% Va and 9% IV. VIII reacted with HgCl₂ in Et₂O, giving 27% Va and 8% IV. A suspension of VII (prepared from 14 millimoles IV) treated 2 days with 30 millimoles Ph₃B in Et₂O gave 68% (Ph₃BH)Na (as indicated by the H evolved on addition of MeOH) and 2.45 g. 5,8-diphenyl-1,2-3,4-dibenzocycloöctatetraene (IX), m. 231-1.5° (from AcOH or Me₂CO). VIII (prepared from 0.56 millimole Va) treated with Ph₃B in Et₂O gave 64% IX. By heating 0.3 millimoles IX in 5 cc. AcOH 10 min. with 2 millimoles CrO₃ in 2 cc. AcOH, followed by addition of H₂O, extraction with Et₂O, evaporation, solution in C₆H₆, chromatographing on Al₂O₃ and eluting with CHCl₃, 69% I was obtained. Shaken 3 hrs. with 0.1 g. Raney Ni, 0.41 millimoles IX in 35 cc. dioxane took up 2 moles H, giving 87% VII. A Stuart-Briegleb calotte model indicates that IX can be free from strain only when the 2 olefin linkages in the cyclotetraene ring show a cis-cis configuration. 18 references.

Justus Liebigs Annalen der Chemie published new progress about 594-81-0. 594-81-0 belongs to bromides-buliding-blocks, auxiliary class Bromide,Aliphatic hydrocarbon chain, name is 2,3-Dibromo-2,3-dimethylbutane, and the molecular formula is C4H6O3, Product Details of C6H12Br2.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Bamford, W. R. published the artcileThe decomposition of p-tolylsulfonylhydrazones by alkali, HPLC of Formula: 594-81-0, the publication is Journal of the Chemical Society (1952), 4735-40, database is CAplus.

p-Tolylsulfonylhydrazones are decomposed by alkali or alkoxide to p-toluenesulfinate and either olefin or aryldiazomethanes. The necessary hydrazones were prepared by refluxing p-MeC₆H₄SO₂NHNH₂ 10 min. with the carbonyl compound in alc. Unless otherwise stated, in the following decompositions the reagent is Na in (CH₂OH)₂ (0.7-1.5N). The following tabulation is in the order, starting carbonyl compound, m.p. of p-tolylsulfonylhydrazone, product of decomposition, % yield: Me₂CO, 153°, CH₂:CHMe, -; cyclohexanone, 156°, cyclohexene, 100; PhCH₂COMe, 134-5°, PhCH:CHMe, 80; (Ph₂CH₂)₂CO, 186°, PhCH:CHCH₂Ph, 95; 1-indanone, 192°, indene, 92; Me₃CCOMe, 155°, (Me₂C:)₂ (as dibromide), 34; camphor, 163-4°, camphene [m. 46°, [α]_D¹⁷ 72.4° (Et₂O)], 94; EzH, 128°, PhCH₂OCH₂CH₂ OH (3,5-dinitrobenzoate, m. 78°), 54 (also p-MeC₆H₄SO₂CH₂Ph, 14); PhCOMe, 148°, (Me-PhC:N)₂ (m. 124°), 85; Ph₂CO, 184°, Ph₂C(OMe)CH₂OH (m.63°,) 14 [also (Ph₂C:)₂]; 9-fluorenone, 180-2° (decomposition), Δ^9,9′-bifluorene, 95; PhCH₂COPh, 143°, [Ph(PhCH₂)C:N]₂, 94; Ac₂, 204° (decomposition),4,5-dimethyl-1-(p-tolylsulfonamido)-1H-1,2,3-triazole (m. 139°), 79; (EtCO)₂, 187° (decomposition), 4,5-dipropyl-1-(p-tolylsulfonamido)-1H-1,2,3-triazole (m. 122-3°), 84; BzAc, 168° (decomposition), 4(or 5)methyl-5(or 4)-phenyl-1-(p-tolylsulfonamido)-1H-1,2,3-triazole (m. 179-81°), 72; Bz₂, 184° (decomposition), (CPh)₂, 73; benzoin, 144-5°, PhCH₂COPh, 65; AcCH₂CO₂Et, 105°, p-MeC₆H₄SO₂CHMeCH₂CO₂H, -; BzCH₂CO₂Et, 108°, p-MeC₆H₄SO₂CHPhCH₂CO₂H, -. The last three were carried out with KOH in (CH₂OH)₂.

Journal of the Chemical Society published new progress about 594-81-0. 594-81-0 belongs to bromides-buliding-blocks, auxiliary class Bromide,Aliphatic hydrocarbon chain, name is 2,3-Dibromo-2,3-dimethylbutane, and the molecular formula is C6H12Br2, HPLC of Formula: 594-81-0.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Schoellkopf, Ulrich published the artcileSyntheses with α-metalated isocyanides, XXXVII. 1-Lithio-1-alkenyl isocyanides and their reactions with electrophiles, Quality Control of 594-81-0, the publication is Justus Liebigs Annalen der Chemie (1977), 1167-73, database is CAplus.

Lithiation of RR1C:CHNC gave RR1C:CLiNC, which, with electrophiles such as MeI, ClSiMe3, and carbonyl compounds gave RR1C:CR2NC (R = Ph, R1 = H, R2 = SiMe3, Me, CO2Et, Bz, CO2Li; R = Ph, R1 = Me, R2 = SiMe3; RR1 = (CH2)4, R2 = SiMe3). I (R3 = R4 = Me, Ph; R3 = Ph, R4 = H) were also prepared in 36-77% yields.

Justus Liebigs Annalen der Chemie published new progress about 594-81-0. 594-81-0 belongs to bromides-buliding-blocks, auxiliary class Bromide,Aliphatic hydrocarbon chain, name is 2,3-Dibromo-2,3-dimethylbutane, and the molecular formula is C6H12Br2, Quality Control of 594-81-0.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Parsons, Brendon A. published the artcileAn optimized procedure for PTFE phase vanishing reactions: an improved reaction design and the use of reagents adsorbed on silica, COA of Formula: C6H12Br2, the publication is Journal of Chemical Research (2015), 39(10), 574-581, database is CAplus.

While the phase-vanishing (PV)-PTFE reaction design works well with a broad range of substrates and reaction conditions, there are occasional problems. A description of the problems and their importance, including their effects on the reaction outcome and ways to address them, are discussed. Details of an improved design, a hybrid of previously reported PV-PTFE and solvent-free PV-PTFE designs, is presented, as well as the use of silica-supported reagents.

Journal of Chemical Research published new progress about 594-81-0. 594-81-0 belongs to bromides-buliding-blocks, auxiliary class Bromide,Aliphatic hydrocarbon chain, name is 2,3-Dibromo-2,3-dimethylbutane, and the molecular formula is C6H12Br2, COA of Formula: C6H12Br2.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary