128574-70-9

Upstream product

• 56667-12-0 (E)-2,2'-dibromostilbene 
• 6630-33-7 ortho-bromobenzaldehyde 
• 655-48-1 DL-1,2-diphenylethane-1,2-diol 
• 36901-75-4 (2-bromobenzyl)triphenylphosphonium bromide 
• 108474-32-4 (E/Z)-α,α'-dibromostilbene 
• 128531-50-0 (1RS,2RS)-1,2-Bis(2-bromophenyl)ethane-1,2-diol 
• 97-72-3 2-Methylpropionic anhydride 
• 3433-80-5 1-Bromo-2-bromomethyl-benzene 
• 95-46-5 2-methylphenyl bromide 

Downstream Products

• 172276-95-8 (S,S)-4,5-bis(2-bromophenyl)-2-bromomethyl-1,3-dioxolane 
• 128574-71-0 (1R,2R)-1,2-bis(2′-bromophenyl)-ethane-1,2-diol 
• 181481-65-2 (10R,11R)-10,11-Bis[(1,1-dimethylethyl)dimethylsiloxy]-10,11-dihydro-5-phenyl-5H-dibenzo[b,f]phosphepine 5-oxide 
• 7156-35-6 (4br,9bc)-4b,9b-dihydrobenzobenzo<4,5>furo<2,3-d>furan 

Relevant academic research and scientific papers

Separation of diol enantiomers - A remarkable influence of water

The water content of iPrOH is shown to have a profound influence on the separation of two enantiomers of 2,2′-dibromohydrobenzoin on a Daicel OJ column. iPrOH containing 0.47% water gives no separation, whereas increasing the amount of water in the eluent to 3.4% effects complete separation. The influence is not general.

NONLINEAR EFFECTS INVOLVING TWO COMPETING PSEUDO-ENANTIOMERIC CATALYSTS: EXAMPLE IN ASYMMETRIC DIHYDROXYLATION OF OLEFINS

Asymmetric catalysis in the case of a mixture of pseudoenantiomeric ligands has been studied in the Sharpless asymmetric dihydroxylation of bis-(ortho-bromo)stilbene.Nonlinear behaviours were observed in this situation, one spectacular case being evidence

Hydrogen Bonding-Assisted Enhancement of the Reaction Rate and Selectivity in the Kinetic Resolution of d,l-1,2-Diols with Chiral Nucleophilic Catalysts

An extremely efficient acylative kinetic resolution of d,l-1,2-diols in the presence of only 0.5 mol% of binaphthyl-based chiral N,N-4-dimethylaminopyridine was developed (selectivity factor of up to 180). Several key experiments revealed that hydrogen bonding between the tert-alcohol unit(s) of the catalyst and the 1,2-diol unit of the substrate is critical for accelerating the rate of monoacylation and achieving high enantioselectivity. This catalytic system can be applied to a wide range of substrates involving racemic acyclic and cyclic 1,2-diols with high selectivity factors. The kinetic resolution of d,l-hydrobenzoin and trans-1,2-cyclohexanediol on a multigram scale (10 g) also proceeded with high selectivity and under moderate reaction conditions: (i) very low catalyst loading (0.1 mol%); (ii) an easily achievable low reaction temperature (0 °C); (iii) high substrate concentration (1.0 M); and (iv) short reaction time (30 min). (Figure presented.).

Copper-catalyzed double intramolecular ullmann coupling for the synthesis of diastereomerically and enantiomerically pure 4b,9b-dihydrobenzofuro[3,2-b]benzofurans

The copper-catalyzed double intramolecular Ullmann coupling of syn-1,2-bis(2-bromoaryl)ethane-1,2-diols with catalytic amounts of CuII oxinate as the copper source, K3PO4 as a base, and KI as a reductant in aqueous acetoni

Selective Pinacol Coupling on Regeneratable Supported Acids in Sole Water

Efficient pinacol coupling was developed in sole water, using a reusable heterogeneous supported acid source and zinc as cheap available metal source. This medium can be easily regenerated up to 10-fold without loss of activity. Moreover, supported acids enhance the selectivity of the pinacol coupling reaction compared with homogeneous acids.

Novel synthesis of pinacols and sulfones promoted by Smi￡ NiCl2 bimetallic system

Smi￡NiCl2 as a reductive system promoted reductive coupling of aryl adehydes and aryl ketone into pinacols in good yields and also promoted coupling reaction of aryl sulfonyl chlorides and active halides into sulfones in good yields.

InCl3/Al mediated pinacol coupling reactions of aldehydes and?ketones in aqueous media

A systematic work on the homo-pinacol coupling reactions of benzophenones, aldehydes, and acetophenones in aqueous media with InCl3/Al is described for the first time, in which various 1,2-diols are obtained in moderate to good yields.

Synthesis and chemistry of enantiomerically pure 10,11-dihydrodibenzo[b,f] thiepines

Several chiral thiepines were efficiently constructed using sulfur diimidazole in combination with a variety of bislithiated carbon fragments. The sulfur atom in these thiepines is found to be unusually unreactive compared to diphenylsulfide. The Royal Society of Chemistry 2006.

Vanadium-catalyzed pinacol coupling reaction in water

A catalytic pinacol coupling using water as a solvent was performed by a catalytic amount of vanadium(III) chloride and metallic Al as a co-reductant. A combination forms a binary catalytic system, being a sharp contrast to the reaction in organic solvent, which requires a chlorosilane as an additive. Various aromatic aldehydes underwent the reductive coupling to give the corresponding 1,2-diols in moderate to good yields.

Synthesis, X-ray structures and chemistry of enantiomerically pure 10,11-dihydro-5-phenyl-5H-dibenzo[b,f]phosphepine 5-oxides

Several phosphepine oxides were synthesised in optically pure form. Sharpless asymmetric dihydroxylation was used to introduce the chiral centres in all cases. Ring closure was achieved using either PhPCl2 or PrPCl2 together with a double nucleophile generated by either a double ortho-lithiation or double bromine-lithium exchange. The X-ray crystal structures of three phosphepine oxides illustrate their different conformations. The NMR spectra of several phosphepine oxides are described as is the chemistry which is shown to differ from that of acyclic phosphine oxides.