Category: 594-81-0

Bestman, HansJuergen published the artcileReactions with phosphinealkylenes. VII. Olefins and ketones by autoxidation of phosphinealkylenes, Quality Control of 594-81-0, the publication is Chemische Berichte (1963), 96(7), 1899-908, database is CAplus.

cf. CA 58, 13788g. Phosphinealkylenes of the type RCH:PPH₃ (R = alkyl) are oxidized by O to olefins and Ph₃PO. Phosphinealkylenes of the type RR’C:PPh₃ (I) yield with O the corresponding ketones. If the autoxidation of the I is interrupted after consumption of 1 O, olefins can also be formed by the Wittig reaction of the resulting ketone with unoxidized I. Ph₃P (26 g.) and 20 g. EtMeCHBr heated 18 hrs. at 100-20° in a sealed tube, and the powd. product boiled 2-3 times with C₆H₆ yielded 38 g. [iso-BuPPh₃]Br (II), m. 235-8° Ph₂P (13 g.) and 9.0 g. hexahydrobenzyl bromide heated 24 hrs. at 140-50° in a sealed tube, and the powd. product washed with pert. ether yielded 21 g. triphenylhexahydrobenzylphosphonium bromide (III), m. 225-8° (with softening from 200°). Ph₃P (26 g.) and 16 g. p-MeOC₆H₄CH₂Cl heated 1 hr. at 80-100°, and the powd. product boiled 2-3 times with C₆H₆ yielded 41 g. [p-MeOC₆H₄CH₂PPh₃]Cl (IV), m. 214-18° (CHCl₃-EtOAc). Ph₃P (26 g.) and 27 g. cyclohexyl bromide heated 60 hrs. at 140° in a sealed tube gave similarly 40 g. triphenylcyclohexylphosphonium bromide (V), m. 255-9° (CHCl₃-EtOAc). NaNH₂ (up to 25% excess) in dry NH₃ treated with the dry, powd. phosphonium salt, the NH₃ evaporated, the residue boiled about 10 min. with C_H6, MePh, Et₂O, tetrahydrofuran, etc., and the solution oxidized with O gave the corresponding oxidation products; method A. Na, K, or Li in 100 cc. absolute MeOH, EtOH, or tert-BuOH treated with an equivalent amount dry, powd. phosphonium salt gave a solution of phosphinealkylene which can be oxidized with O; method B. All operations up to the oxidation have to be performed under N or Ar. The oxidations with O were carried out in a special apparatus (described in detail) in which a measured amount O can be recirculated. [PhCH₂PPh₃]Br (18.0 g.) and 0.92 g. Na in 100 cc. absolute EtOH processed by method B, and the refluxing ylide solution treated 24 hrs. with 0 and poured into 100 cc. 10% HBr precipitated 1.46 g. trans-stilbene (VI), m. 121°; the filtrate evaporated, the residue extracted with Et₂O, the extract diluted with petr. ether, the precipitated Ph₃PO (10.3 g.) filtered off, and the filtrate distilled gave 0.84 g. cis-stilbene (VII), b₁₂ 140-2°, n²⁰_D 1.6189. Tricyclohexylbenzylphosphonium chloride (8.1 g.) treated with 0.46 g. Na in 50 cc. absolute EtOH by method B and oxidized 12 hrs. at reflux, and the mixture poured into 50 cc. 10% HBr gave 1.2 g. VI; the acidic mother liquor concentrated gave 1.2 g. unchanged phosphonium salt and 74% tricyclohexylphosphine oxide. [¹PhCH₂PPh₃]Cl treated with 0.6 g. Na and 70 cc. C₆H₆ by method A, the solution oxidized 5 hrs. at 80° (96% O consumption) and evaporated, and the residue dissolved in 30 cc. MeOH and poured into 20 cc. 10% HBr yielded 1.7 g. VI and only a small amount of VII; the mother liquor diluted with H_O precipitated 5.8 g. Ph₃PO. IV (12.5 g.), 1.2 g. Na, and 150 cc. dry C₆H₆ processed by method A, and the solution oxidized 1 hr. at room temperature (84% O consumption) yielded 1.4 g. trans-(MeOC_H4CH:)₂, m. 210-11° (MeOH-H₂O); the mother liquor evaporated and the residue triturated with petr. ether left 6.9 g. Ph₃PO; the petr. ether extract distilled yielded 0.70 g. cis-p-(MeOC₆H₄CH:)₂, b_0.1 140°, m. 35°. [EtPPh₃]Br (11.1 g.) treated by method A with 0.9 g. Na in 150 cc. dry Et₂O and oxidized 15 min. at 0% and the effluent gas (swept with N) passed into BrCHCl₃ yielded 2.7 g. (MeCHBr)₂, b₁₂ 58-62°; the Et₂O solution yielded 6.2 g. Ph₃PO₂. [PrPPh₃]Br (11.7 g.) treated by method A with 0.9 g. Na and 100 cc. MePh and oxidized 15 min. at 0° (100% O consumption) yielded 0.90 g. 3-hexene, b. 63-5°. [BuPPh₃]Br (24 g.) treated with 1.8 g. Na and 150 cc. dry tetrahydrofuran by method A and oxidized 0.5 hr. at room temperature (92% O consumption) gave 14.8 g. Ph₃PO and 2.6 g. cis- and trans-4-octene, b₇₁₀ 117-18°; dibromide b₁₀ 103°. III (22.0 g.), 1.8 g. Na, and 150 cc. C₆H₆ processed by method A and oxidized 25 min. at room temperature (100.% O consumption) yielded 11.0 g. Ph₃PO, 0.80 g. hexahydrobehzaldehyde, b₁₅ 50-3° (2,4-dinitrophenylhydrazone m. 111-13°), and 2.9 g. cis- and trans-1,2-dicyclohexylethylene. [iso-PrPPh₃]Br (VIII) (15.8 g.) treated with 0.7 g. Na and 100 cc. MePh by method A and oxidized 5 min. at room temperature (80% O consumption) and the mixture distilled into aqueous 2,4-(O₂N)₂C₆H₃NHNH₂ gave 2.2 g. 2,4-(O₂N)₂C₆H₃NHN:CMe₂, m. 126°; the distillation residue evaporated and the residue triturated with 50 cc. petr. ether yielded 2.6 g. Ph₃PO. VIII (15.2 g.) treated by method A with 1.3 g. Na in 200 cc. dry C₆H₆, 1/2 of the resulting solution oxidized with O, the O.removed with N, the remaining unoxidized reaction solution added, the mixture distilled, and the distillate treated with Br yielded 2.8 g. (Me₂CBr)₂, m. 168-71° (EtOH); the distillation residue gave 6.7 g. Ph₃PO. The same result was obtained when the oxidation was interrupted after the consumption of 1 equivalent O and the mixture was kept several hrs.; 53% yield. VIII (6.0 g.) processed with 0.5 g. Na and 100 cc. MePh by method A and oxidized 10 min. at room temperature (75% O consumption), and distilled into aqueous 2,4-(O₂N)₂C₆H₃NHNH₂.HCl yielded 2.1 g. 2,4-(O₂N)₂C₆H₃NHN:CEtMe, m. 116-17°; the residue gave 3.5 g. Ph₃PO. VIII (16.0 g.) treated by method A with 1.4 g. Na and 200 cc. dry C₆H₆, 1/2 of the resulting solution oxidized, purged with N, treated with the remaining unoxidized solution, refluxed under N until pale yellow, and evaporated, and the residue treated with 100 cc. Et₂O and cooled gave 9.6 g. Ph₃PO; the filtrate distilled yielded 1.3 g. (EtMeC:)₂, b. 95-8° [dibromide b₇₆₀ 147-50° (slight decomposition)]; the same results were obtained when the oxidation was interrupted after the consumption of 1 equivalent O; 50% yield. [MePhC:PPh₃]Br (8.9 g.) treated with 0.7 g. Na and 100 cc. dry C₆H₆ by method A and oxidized 15 min. at room temperature (98% O consumption) yielded 4.2 g. Ph₃PO; the filtrate evaporated, and the residue treated with EtOH and 2,4-(O₂N)₂C₆H₃NHNH₂ solution gave 4.1 g. 2,4-(O₂N)₂C₆H₃NHN:-CMePh, m. 248°. [Ph₂CHPPh₃]Br (7.6 g.) treated with 0.6 g. Na and 200 cc. dry C₆H₆ by method A and oxidized 8 hrs. at room temperature (95% O consumption), the C₆H₆ distilled, and the residue treated with 60 cc. petr. ether yielded 3.1 g. Ph₃PO; the filtrate evaporated and the residue treated with 2,4-(O₂N)2C₆H₃NH-NH₂.H₃PO₄ solution yielded 3.8 g. 2,4-(O₂N)2C₆H₃NHN:CPh₂, m. 238°. V (8.5 g.) treated with 0.7 g. Na and 100 cc. C₆H₆ by method A and oxidized 15 min. at room temperature (77% O consumption), and the mixture worked up in the same manner gave 3.6 g. cyclohexanone 2,4-dinitrophenylhydrazone, m. 158°.

Chemische Berichte 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

Yasu, Yusuke published the artcileSunlight-driven synthesis of γ-diketones via oxidative coupling of enamines with silyl enol ethers catalyzed by [Ru(bpy)₃]²⁺, Synthetic Route of 594-81-0, the publication is Chemical Communications (Cambridge, United Kingdom) (2012), 48(43), 5355-5357, database is CAplus and MEDLINE.

A photosensitizer [Ru(bpy)₃]²⁺ catalyzes oxidative coupling reaction of enamines with silyl enol ethers under visible light irradiation by a Xe lamp or sunlight to produce γ-diketones. A 2e-oxidation process involved in this reaction is achieved by a combination of the photoexcited [Ru(bpy)₃]²⁺ species and duroquinone, a 2e-acceptor.

Chemical Communications (Cambridge, United Kingdom) 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 C65H82N2O18S2, Synthetic Route of 594-81-0.

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

Brueckner, Alexander C. published the artcileVisible-light-mediated, nitrogen-centered radical amination of tertiary alkyl halides under metal-free conditions to form α-tertiary amines, Product Details of C6H12Br2, the publication is Organic & Biomolecular Chemistry (2016), 14(19), 4387-4392, database is CAplus and MEDLINE.

A mild and operationally convenient amino-functionalization of a range of tertiary alkyl halides by reaction with iminoiodinanes (PhI=NNs) and I₂ was developed. According to the mechanistic experiments described within the reaction was speculated to proceed through a light-promoted, N-centered radical pathway involving a N,N-diiodosulfonamide reactive species. This method of direct N-incorporation offers an attractive alternative to the production of α-tertiary amines, a synthetically challenging structural class found in a variety of bioactive mols.

Organic & Biomolecular Chemistry 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, Product Details of C6H12Br2.

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

Kofron, William G. published the artcileDisplacement on halogen vs. carbon and on halogen vs. hydrogen of certain polyhalides by diphenylmethide ion in liquid ammonia, Name: 2,3-Dibromo-2,3-dimethylbutane, the publication is Journal of the American Chemical Society (1968), 90(15), 4126-9, database is CAplus.

Na and K diphenylmethide (I), prepared from diphenylmethane (II) and the corresponding alkali amide in liquid NH3 underwent displacement on halogen with ethylene bromide and iodide to form the dimer, 1,1,2,2-tetraphenylethane (III), and presumably ethylene; in contrast, I underwent displacement on C (SN2) with ethylene chloride to give the twofold alkylation product. Similarly, potassio salt I underwent displacement on halogen with 2,3-dibromo-2,3-dimethylbutane, 1,1,2,2-tetrabromoethane, and hexachloroethane to form dimer III and an olefinic product. The olefinic products from the tetrabromo- and hexachloroethanes were dibromoethylene and tetrachloroethylene, resp., potassio salt I also underwent displacement on halogen with these olefinic halides to afford apparently acetylene. Potassio salt I underwent diplacement on H with 1,1-dichloroethane to regenerate II, and displacement on halogen with 1,1,1-trichloroethane and benzotrichloride to form a mixture of II and III; in these cases the halide was converted to an alddimine. Potassio salt I underwent displacement on halogen with N-bromosuccinimide to give dimer III and succinimide.

Journal of the American 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, Name: 2,3-Dibromo-2,3-dimethylbutane.

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

Altona, Cornelis published the artcileConformation of open chain compounds. II. Dipole moments and conformational equilibrium of some vicinal dibromides, the benzene effect, Category: bromides-buliding-blocks, the publication is Recueil des Travaux Chimiques des Pays-Bas (1968), 87(3), 279-88, database is CAplus.

The dipole moments of 6 title compounds such as CH2BrCH2Br and Me3CHBrCH2Br, were measured in CCl4 and C6H6. The gauche Br….Br interaction energy was solvent dependent; its value was 380 ± 30 cal./mole lower in C6H6 than in CCl4.

Recueil des Travaux Chimiques des Pays-Bas 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

Altona, C. published the artcileConformation of open-chain compounds. III. Carbon-halogen stretching frequencies and conformation of some vicinal dihalides, Computed Properties of 594-81-0, the publication is Recueil des Travaux Chimiques des Pays-Bas (1969), 88(1), 33-42, database is CAplus.

Hal = halogen throughout. A study of the ir and Raman spectra of some vicinal dihaloethanes, propanes and butanes with predominant antiperiplanar orientation in the straight chain and branched series, reveals that the 2 C-Hal stretching frequencies occur characteristically as a more or less strongly coupled pair: an intense Raman band (νs) and a strong ir active mode of vibration (νas) at lower frequency. The C-Hal frequencies of the gauche conformations are weakly coupled. The position of the bands and the difference Δν = νs – νas are functions of the chem./geometrical structure in the vicinity of the C-Hal bonds. Empirical rules are presented by which the C-Hal frequencies or, in strongly coupled systems, the average frequency of anti as well as of gauche forms can be predicted with fair accuracy.

Recueil des Travaux Chimiques des Pays-Bas 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

Kelso, Robert G. published the artcileThe synthesis and properties of 1,1,2-trimethylcyclopropane, Category: bromides-buliding-blocks, the publication is Journal of the American Chemical Society (1952), 287-92, database is CAplus.

The reaction between Me₂CBrCH₂CHBrMe and Zn in aqueous PrOH at 0° carried out on a large scale permitted a thorough study of the reaction products. 1,1,2-Trimethylcyclopropane (I) comprised 68% of the hydrocarbon mixture obtained in 67% yield. Me₂CHPr, CH₂:CMePr (II), b₇₆₀ 61°, n_D²⁵ 1.3916, and Me₂C:CHEt, b₇₆₀ 64.5-5.5°, n_D²⁵ 1.3987-1.3995, were also obtained; MeCH:CHCHMe₂ was present in minor amount Com. Me₂C(OH)CH₂CH(OH)Me (18 moles) and PBr₃ yielded 4112 g. crude Me₂CBrCH₂CHBrMe (III), b₅ 65-70°, n_D²⁰ 1.496-1.498. (CMe:CH₂)₂, and anhydrous HBr yielded 70% H₂CBrCHMeCBrMe₂, b₁₀ 76°, and 30% (CBrMe)₂, m. 160-4°, b₁₀ 78°. The product of AcII and Me₂CH₂CHO reduced over Raney Ni at 70° and 1500 lb./sq. in. yielded 13% MeCH(OH)CMe₂CH₂OH (IV), b₂₀ 121°, n_D²⁰ 1.4408; IV with PBr₃ at 0° yielded MeCHBrCH₂CBrMe₂. The following constants were determined: for I, f.p., -138.27°, m.p. -138.30°, b₇₆₀ 52.55, dt/dp 0.039, d₄²⁰ 0.6947, n_D²⁰ 1.3864, dn_D/dt 0.00054, n_D²⁵ 1.3834; for CH₂:CMeCHMe₂, b₇₆₀ 55.6°, n_D²⁵ 1.3874; for (Me₂C:)₂, b₇₆₀ 73.3°, n_D²⁵ 1.4070.

Journal of the American 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, Category: bromides-buliding-blocks.

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

Kiprianov, G. I. published the artcileSynthesis of some derivatives of β-phenylisopropylamine. I. Reaction of symmetric dihaloalkanes with β-phenylisopropylamine, COA of Formula: C6H12Br2, the publication is Ukrains’kii Khemichnii Zhurnal (1950), 16(No. 6), 620-6, database is CAplus.

Heating 5 g. (CH₂Br)₂ with 35 g. PhCH₂CHMeNH₂ (I) 5 hrs. at 130° gave 7.4 g. (CH₂NHCHMeCH₂Ph)₂, b₃ 195-200°; di-HCl salt, m. 272-4°. Heating 37.5 g. I with 17 g. (CMe₂Br)₂ 6 hrs. on a steam bath gave 5.6 g. PhCH₂CHMeNHCMe₂CMe:CH₂, b₇ 135-43°; HCl salt, m. 173-4°; the free amine with Br yields a product m. 120-1°. Heating 67.5 g. I with 12 g. 1,2-dibromocyclohexane 7 hrs. at 100° and 4 hrs. at 120° gave 7.2 g. N-(1-(or 2-)cyclohexen-1-yl)-2-phenylisopropylamine, b₃ 130-5°; HCl salt, m. 186-9°. (CH₂)₃Br₂ (10.1 g.) and 67.5 g. I kept 24 hrs. at room temperature gave 10 g. 1,3-bis(2-phenylisopropylamino)propane, b₂ 200-5°; di-HCl salt, m. 238-9°. Similarly (CH₂)₄Br₂ gave 94% 1-(2-phenylisopropyl)pyrrolidine, b₄ 117-23°; HCl salt, m. 136-8°. (CH₂)₅Br₂ gave 62% 1-(2-phenylisopropyl)piperidine, b₄ 115-17°; HCl salt, m. 215-16°. (CH₂)₆Br₂ and I kept 24 hrs. at room temperature gave 58% 1,6-bis(2-phenylisopropylamino)hexane, b₂ 224°; picrate, m. 183-4°; di-HCl salt m. 253-4°.

Ukrains’kii Khemichnii Zhurnal 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

Chenede, Alain published the artcileCationic rearrangements controlled by the presence of a silyl group, Recommanded Product: 2,3-Dibromo-2,3-dimethylbutane, the publication is Journal of Organometallic Chemistry (2003), 686(1-2), 84-93, database is CAplus.

1,1-Disilylcarbinols having two alkyl groups on the adjacent carbon atom react with thionyl chloride in sulfur dioxide to give the product in which one of the alkyl groups has migrated towards the two silyl groups, and one of the silyl groups has been removed from the resultant cation. The reaction is seen in ring-expansion, as in the conversion of cyclohexylbis[dimethyl(phenyl)silyl]carbinol into 1-dimethyl(phenyl)silylcycloheptene, and in open chains, as in the conversion of 1,1-bis[dimethyl(phenyl)silyl]-2-methylpropanol into (E)- and (Z)-2-dimethyl(phenyl)silylbut-2-ene. Phenyldimethylsilyllithium reacts with pinacolone to give the α-silyl carbinol, which rearranges in the same way to give 2,3-dimethylbut-2-ene, effectively achieving a pinacolone-to-pinacol rearrangement.

Journal of Organometallic Chemistry 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

O’Connell, Kathleen M. published the artcileElectron-transfer reactions and associated conformational changes. Electrochemical reduction of some vicinal dibromides, Computed Properties of 594-81-0, the publication is Journal of the American Chemical Society (1983), 105(6), 1473-81, database is CAplus.

The effect of mol. conformation on the electrochem. reduction of derivatives of trans-1,2-dibromocyclohexane and substituted 1,2-dibromoethanes was studied by low-temperature cyclic voltammetry. Reduction via conformations with antiperiplanar Br atoms is preferred, and conformational interconversion prior to electron transfer was observed in trans-1,2-dibromo- (I) and 1,1-dimethyl-trans-3,4-dibromocyclohexane (II), meso– and dl-Ph(CHBr)₂Ph (meso– and dl–III), and Br(CMe₂)₂Br (IV). Digital simulation of the low-temperature voltammetric data provided thermodn. and kinetic information on the conformational interconversion in I, II, III, and IV. The energy barriers to conformational interconversion in meso– and dl-Me(CHBr)₂Me (meso– and dl–V) are quite small, and conformational effects in the electrochem. reduction of V could not be detected at -135°. 1-Methyl-cis-3,trans-4- (VI) and –trans-3,cis-4-dibromocyclohexane (VII) and meso– and dl-Me₂CH(CHBr)₂CHMe₂ (meso– and dl–VIII) exist almost entirely in a single conformation. Voltammetric peak potentials of VI, VII, and meso– and dl–VIII reflect the geometry of their principal conformation.

Journal of the American 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, Computed Properties of 594-81-0.

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