Styrene, p-bromo

CAS 103-64-0 EINECS/ELINCS 203-131-3 Synonyms 1-Bromo-2-p-phenylethylene a-Bromo-p-phenylethylene u-Bromostyrene Bromostyrol Bromostyrolene (2-Bromovinyl) benzene Bromstyrol p-Bromstyrol Bromstyrole Hyacinth base Styrene, p-bromo-... 

Styrene biock poiymerwith 1,3-butadiene, hydrogenated. See Hydrogenated styrene/2-methyi-1,3-butadiene biock poiymer Styrene, p-bromo-. See P-Bromostyrene Styrene, p-bromo-p-nitro-. See P-Bromo-P-nitrostyrene... 

Betzemeier et al. (1998) have used f-BuOOH, in the presence of a Pd(II) catalyst bearing perfluorinated ligands using a biphasic system of benzene and bromo perfluoro octane to convert a variety of olefins, such as styrene, p-substituted styrenes, vinyl naphthalene, 1-decene etc. to the corresponding ketone via a Wacker type process. Xia and Fell (1997) have used the Li salt of triphenylphosphine monosulphonic acid, which can be solubilized with methanol. A hydroformylation reaction is conducted and catalyst recovery is facilitated by removal of methanol when filtration or extraction with water can be practised. The aqueous solution can be evaporated and the solid salt can be dissolved in methanol and recycled. 

Direct irradiation at 254 nm of 1-phenylpropene 93a in cyclohexane affords a Z/E mixture in a ratio of 65 35 [223], whilst photosensitized isomerization of 93a gives (Z/E)pss ratios of 55 45 and 88 12 upon benzophenone and chrysene sensitization, respectively (Sch. 37). Similarly, a variety of P-alkylstyrenes has been subjected to triplet sensitization [224,225]. Upon direct irradiation of ( )-P-bromo-P-nitro-styrenes, the (Z)-isomers are obtained in 40-50% yield, but the major... 

The kinetics of dehydrohalogenation from the configurational isomers of vinyl halides have been determined for numerous reactions. Thus cw-/7-nitro-P-bromo-styrene in the presence of ethanolic NaOH is converted quantitatively by trans elimination to /7-nitrophenylacetylene within a few minutes (equation 21), whereas the trans isomer hardly reacts at all in that short time. However, the latter affords l,l-diethoxy-2-p-nitrophenylethane in high yield when kept under the above conditions for 20 days (equation 22). The mechanism of the latter reaction could not... 

However, when the organometallic reagent was prepared by reaction of n-butyllithium on p-bromo styrene, a more complex reaction system resulted. Only a very poor yield of 1,4-diphenylbutadiyne (189) was obtained, together with various amounts of phenylacetylene. 10... 

Poly(ethyl methacrylate) Poly[oxy(2,6-dimethyl-l,4-phenylene)] Poly(p-bromo styrene)... 

Poly(cyclohexyl methacrylate) Poly(p-bromo styrene)... 

In an effort to develop a green Hunsdiecker reaction, synthesis of p-bromo-styrenes was accomplished from the reaction of a,p-unsaturated aromatic carboxylic acids with KBr and H2C>2 catalyzed by Na2MoCV2H20 in aqueous medium.33... 

In some cases the addition of bromide to alkene radical cations is reversible. For example, the addition of bromide to the p-methyl-4-methoxystyrene radical cation occurs reversibly, as demonstrated by the formation of the radical cation when the P-bromo radical is generated independently by photolysis of l-(4-methoxyphenyl)-l,2-dibtomopropane (Eq. 18). An equilibrium constant of 2 x 10 M has been measured for the loss of bromide from this radical in acetonitrile. The apparent lack of reactivity of 1,3-dioxole radical cations with bromide ion in water has also been explained on the basis of reversible addition with rapid loss of bromide from the product radical. However, on the basis of the solvent effects noted above, it is also possible that the lack of reactivity in water is a solvent effect since decreases in reactivity of 4 to 5 orders of magnitude have been observed for reactions of bromide ion with styrene radical cations in largely aqueous solvent mixtures. - ... 

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