40957-21-9

Upstream product

• 530-48-3 1,1-Diphenylethylene 
• 106896-07-5 1,2,3-triphenylbenzothiophenium tribromide 

Downstream Products

• 74249-43-7 3-(2-bromo-1,1-diphenylethoxy)propene 
• 162129-87-5 (2-bromo-1-methoxyethane-1,1-diyl)dibenzene 
• 10035-10-6 hydrogen bromide 
• 82668-86-8 2,2-diphenyl-4-methyltetrahydrofuran 
• 82668-87-9 4,4-dimethyl-2,2-diphenyltetrahydrofuran 
• 13249-58-6 1-bromo-2,2-diphenylethylene 
• 1450-63-1 1,1,4,4-tetraphenyl-1,3-butadiene 
• 74249-44-8 2-(2-methyl-2-propenyloxy)-2,2-diphenylethyl bromide 
• 530-48-3 1,1-Diphenylethylene 

Relevant academic research and scientific papers

Hexamethonium bis(tribromide) (HMBTB) a recyclable and high bromine containing reagent

A recyclable and high bromine containing di-(tribromide) reagent, hexamethonium bis(tribromide) (HMBTB) has been synthesized and utilized for the bromination of various organic substrates. The spent reagent hexamethonium bromide (HMB) can be effectively recycled by regenerating and reusing it without significant loss of activity. The crystalline and stable bis(tribromide) is an effective storehouse of very high percentage of active bromine requiring just half an equivalent of it for complete bromination. Both the Br3- moieties in HMBTB are nearly linear with Br-Br-Br angle of 179.55°.

Selective aerobic oxidative dibromination of alkenes with aqueous HBr and sodium nitrite as a catalyst

Various alkenes (internal, terminal, aryl and alkyl substituted) and 1,2-diphenylethyne were efficiently and selectively dibrominated using 2 equivalents of 48% aqueous hydrobromic acid, with air as an oxidant and sodium nitrite as a catalyst. Despite the presence of water, only trans dibromination occurred producing anti-1,2-dibromoalkanes and (E)-1,2-dibromo-1,2- diphenylethene. A comparison of resource demand, waste production and environmental, health and safety issues of the NaNO2 catalyzed aerobic bromination with molecular bromine and other oxidative bromination methods revealed that the proposed method is not only selective and effective but has a better environmental profile.

A new recyclable ditribromide reagent for efficient bromination under solvent free condition

1,2-Dipyridiniumditribromide-ethane (DPTBE) has been synthesized and explored as a new efficient brominating agent. The crystalline ditribromide reagent is stable for months and acts as a safe source of bromine requiring just 0.5 equiv for complete bromination. It has high active bromine content per molecule and shows a remarkable reactivity compared to other tribromide reagents toward various substrates by just grinding the reagent and substrates in a porcelain mortar at room temperature. No organic solvent has been used during any stage of the reaction for substrates giving product as solid. Product can easily be isolated by just washing the highly water soluble 1,2- dipyridiniumdibromide-ethane (DPDBE) from the brominated product. The spent reagent can be recovered, regenerated, and reused without any significant loss.

2,2-(Diaryl)vinylphosphine compound, palladium catalyst thereof, and process for producing arylamine, diaryl, or arylalkyne with the catalyst

A novel 2,2-(diaryl)vinylphosphine compound represented by the following general formula (1): (wherein R1 is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alicyclic group having 5 to 7 carbon atoms, etc.; R2, R3, R4, R5, R6, and R7 may be the same or different and each is an alkyl group having 1 to 6 carbon atoms, an alicyclic group having 5 to 7 carbon atoms, etc., provided that R4 and R5 taken together and/or R6 and R7 taken together may represent a fused benzene ring, a substituted fused benzene ring, a trimethylene group, etc.; and p, q, r, and s each is 0 to 5, provided that p+q and r+s each is in the range of from 0 to 5); a palladium-phosphine catalyst obtained by causing a palladium compound to act on the novel 2,2-(diaryl)vinylphosphine compound; and a process for obtaining an arylamine, a diaryl and an arylalkyne in the presence of the palladium-phosphine catalyst.

A kinetic, product and kinetic isotope effect investigation of the bromination of 1,1-diphenylethyIenes and of their 2,2-dideuterio derivatives

The kinetics of bromination of 1,1-diphenylethylene (1a), 4-trifluoromethyl-1,1-diphenylethylene (1b), and 1-(3-trifluoromethylphenyl)-1-(4-trifluoromethylphenyl)ethylene (1c) and of their 2,2-dideuterio derivatives have been investigated in 1,2-dichloroe

Formation of Bromocarbenium Bromide Ion Pairs in the Electrophilic Bromination of Highly Reactive Olefins in Chlorinated Aprotic Solvents

The kinetics and the products of bromination of several substituted stilbenes with tetrabutylammonium tribromide (TBAT) have been investigated in aprotic solvents at different temperatures. Stilbenes bearing electron-withdrawing or moderately electron-donating substituents gave stereospecifically the anti addition products. The reactions followed a second-order rate law, and an inverse kinetic isotope effect (KIE), kH/kD = 0.85(0.05), was found for the bromination of cis-stilbene. The reactions of cis- and trans-4,4-dimethoxystilbenes yielded mixtures of meso and d,l dibromides both in chloroform and 1,2-dichloroethane. The rate constants (kBr3-) measured for the latter olefins deviated considerably from the Hammett correlations, and added bromide had a significant effect on the rates. The reactions of these activated stilbenes with molecular Br2, carried out at low Br2 concentration, followed a mixed second/third-order rate law. The kinetic and product distribution data for the reaction, with TBAT, of stilbenes bearing electron-withdrawing or moderately electron-donating substituents are interpreted on the basis of the known mechanism involving a product-and rate-determining nucleophilic attack by bromide on the olefin-Br2 π-complex. The data related to the bromination of the more activated methoxystilbenes are rationalized considering that, for these olefins, even in aprotic solvents, the ionization of the initially formed 1:1 π-complex to a bromocarbenium bromide ion pair can compete both with the formation of a bromonium-tribromide ion pair and with the nucleophilic attack by Br-. For this second-order process (first order in Br2), the kinetic constants and the activation parameters have been measured in chloroform and 1,2-dichloroethane and the activation parameters have been compared with those related to the third-order Br2 addition and to the reaction with TBAT.

FORMATION OF 1-ARYL-1-BENZOTHIOPHENIUM IONS IN BROMINATION OF o-ARYLTHIOPHENYL-SUBSTITUTED ETHYLENES

Bromination reaction of o-arylthiophenyl-substituted ethylenes gave 1-aryl-1-benzothiophenium ions by intramolecular cyclization in the brominium intermediates.The substituent and solvent effects are also discussed.

UNE NOUVELLE METHODE DE BROMATION : LE TRIBROMURE DE TETRABUTYLAMMONIUM.

Tetrabutylammonium tribromide (TBA Br3) is used under mild conditions as bromating agent for the addition on double bonds of alkenes and for selective α-substitution of acetals in high yields.

Selectivity Relationships and Substituent-Substituent Interactions in Carbocation-Forming Bromination. The Transition-State Contribution to the ρ Variation

For arylolefin bromination through benzylic carbocations, X-C6H4-C+(R)-CHBr-R', there are 18 reaction constants, ρR, describing ring-substituent effect X, which vary from -1.6 to -5.9 depending on R and R' (H, Me, OMe, or Ar').This r