4-Bromobenzene sulfonic acid

This method is a modification of that of Buckles, Hausman, and Wheeler.2 4,4 -Dibromobiphenyl has also been prepared by the bromination of biphenyl in water,3 carbon disulfide,4 and glacial acetic acid 6 by the bromination of a mixture of biphenyl-sulfonic acids in dilute sulfuric acid 6 by the action of sodium carbonate on the perbromide obtained from the reaction of di-azotized benzidine with bromine water 7 and by passing />-di-bromobenzene vapor through a red-hot tube.8... 

Fumaric acid is photostable in the solid state. Its ammonium salt, however, photoreacted to give the syn [2-1-2] cyclobutane dimer (Scheme 50) [83]. N-(l-Octadecyl)-4-stilbazolium p-chloro- or p-bromobenzene sulfonate underwent quantitative photodimerization to give the syn head-to-head dimer (Scheme 51) [84]. The structure of the dimers from these photodimerization reactions indicates that a compulsory control of the stereochemistry by steric and coulombic repulsion was unsuccessful in these cases. We are now looking for other crystallographic strategies to synthesize the all-tranj-cyclobutane dimer of fumaric acid. 

Table 8. Rates of Solvolysis of p-Bromobenzene-sulfonates in Acetic Acid" ...

Studies by Kiersznicki and co-workers demonstrated that chlorosulfonic acid is an effective catalyst in the alkylation of arenes by reaction with alkenes. Benzene, toluene and ethylbenzene were alkylated by propene, elhene and 2-butene in the presence of chlorosulfonic acid which strongly catalysed the alkylations and inhibited polyalkylation. Increasing the concentration of the catalyst enhanced the proportion of /7-isomers in the products. Fluoro-, chloro-and bromobenzenes were similarly alkylated by reaction with C2-C4 alkenes using chlorosulfonic acid as catalyst. The optimum alkylation conditions were with a halobenzene alkene ratio of 1 0.25, a catalyst concentration of 0.33 mol mol" of fluorobenzene and 0.5 mol mol of the other halobenzenes, a temperature of 70 C and a reaction time of 2 hours. Alkylation with propene gave haloisopropylbenzenes the monoalkyl products were obtained as o-, m- and p- mixtures, the relative amounts depended on the quantity of catalyst used and the by-products were dialkyl derivatives, sulfonic acids and sulfones. In the reaction of benzene with propene, fluorosulfonic acid was a more potent alkylation catalyst than chlorosulfonic acid. ... 

Using the optimal conditions for the radical terpolymerization of 4-[(a,/ ,/ -trifluorovinyl)oxy]bromobenzene with the fluoroalkenes, these authors reported the synthesis of new polymer electrolyte membranes based on fluoropolymers incorporating aromatic perfluorovinyl ether sulfonic acids [85,107]. In fact, a novel synthetic route for the preparation of perfluorovinyl ether monomer containing sulfonic functionalities, 4-[(a,, -trifluorovinyl)oxy]benzenesulfonic acid (TFVOBSA), was proposed. This monomer was synthesized in 72% overall yield. Further, the radical (co)- and terpolymerization of 4-[(a,, -trifluorovinyl)oxy] benzenesulfonyl chloride (TFVOBSC) with VDF, HFP, and PMVE (Fig. 2.25)... 

For carbon nanotubes, organosoluble PS-SWCNT nanocomposites [292] have been prepared that could be efficiently transformed to highly hydrosoluble, pH-responsive materials via direct sulfonation of the grafted PS chains [296]. In another approach, MWCNT-C H was clicked with azide-functionalized poly(glycerol methacrylate) and the final hairy MWCNTs were used for the in situ synthesis and immobilization of monodisperse 3 nm-sized palladium nanoparticles. The final heterostructure had a high catalytic activity (77%) for the C-C coupling Suzuki reaction between 4-bromobenzene and phenyl boronic acid [293],... 

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