Bromide in water

Another approach is therefore to adopt a model process that is very similar to the reactions of interest. Swain and Scott ° selected as a standard reaction the nucleophilic substitution reaction of methyl bromide in water at 25°C. 

The heat of solution of silver bromide in water at 25°C is 20,150 cal/mole. Taking the value of the entropy and the solubility of the crystalline solid from Tables 44 and 33, find by the method of Secs. 48 and 49 the difference between the unitary part of the partial inolal entropy of the bromide ion Br and that of the iodide ion I-. 

The solvent can also affect regioselectivity. Consider O- vs C-alkylation of phenoxide ion with allyl chloride or bromide. In water, with allyl chloride the O- to C-alkylation ratio is 49 41 with phenol as a solvent it is 22 78 with methanol, dimethylformamide, and dioxane 100% O-alkylation is achieved. The selective solvation of the more electronegative O by the more protic solvents perhaps leads to some C-alkylations. 

Gross et al. [3] and Reid et al. [30] measured surface tension of the water-nitrobenzene interface in the presence of bromides of sodium and tetra-alkylammonium ions in water and tetra-alkylammonium tetraphenylborates in nitrobenzene, i.e., tetra-alkylammonium served as the potential-determining ion, cf. the scheme (13). The surface tension vs. the potential difference A p plot (electrocapillary curve), cf. Eq. (15), was constructed by varying the concentration of tetra-alkylammonium bromide in water, while holding... 

Indium-mediated coupling of sulfonyl chlorides with alkyl bromides in water readily generates sulfones.89 Sulfones can also be obtained via... 

The indium-mediated allylation of trifluoroacetaldehyde hydrate (R = H) or trifluoroacetaldehyde ethyl hemiacetal (R = Et) with an allyl bromide in water yielded a-trifluoromethylated alcohols (Eq. 8.56).135 Lanthanide triflate-promoted indium-mediated allylation of aminoaldehyde in aqueous media generated (i-airiinoalcohols stereoselectively.136 Indium-mediated intramolecular carbocyclization in aqueous media generated fused a-methylene-y-butyrolactones (Eq. 8.57).137 Forsythe and co-workers applied the indium-mediated allylation in the synthesis of an advanced intermediate for azaspiracids (Eq. 8.58).138 Other potentially reactive functionalities such as azide, enone, and ketone did not compete with aldehyde for the reaction with the in situ-generated organo-indium intermediate. 

Scheme 4 Silane mediated reduction of a bromide in water...

Diammino-cadmium Bromide, [Cd(NH3)2]Br2, is obtained in small colourless crystals by saturating a concentrated solution of cadmium bromide in water with ammonia and allowing the solution to evaporate. The compound is unstable and loses ammonia on heating, and on treatment with water is partially decomposed with formation of cadmium hydroxide. The same product is formed by saturating an acetone solution of cadmium bromide with ammonia gas.1... 

Ionescu et al.J measured the CMC of hexadecyl trimethyl ammonium bromide in water-dimethyl sulfoxide (DMSO) mixtures at 25 and 40°C ... 

A. F. Joseph found that the solubility of potassium bromide in water is increased by the addition of bromine. For moderate cone., about half a mol. of bromide is dissolved for each mol. of bromine added to the water. This... 

As in the case of hydrogen chloride, the effect of press, on the solubility of hydrogen bromide in water is not in accord with Henry s law. Thus, H. W. B. Roozeboom found that at 0°, a gram of hydrogen bromide at 5 mm. press. 2 504 at 380 mm. 2 116 at 540 mm. and 2 212 at 760 mm. press. He also examined the press.-temp, concentration curves. 

According to W. Herz and G. Anders,32 sat. soln. of potassium bromide in water and methyl alcohol at 25° contain respectively 4 708 and 0 142 mols. per litre the soln. have respectively the sp. gr. 1 37927 and 0 80493 referred to water at 4° the relative viscosities, 1 062 and 0 697, the relative eq. conductivities 91 3 and 57 9 and the specific conductivities. 0 4297 and 0 00825. P. Dutoit and A. Levier have measured the conductivities of soln. in acetone, and hence inferred that in this solvent potassium bromide is much less ionized than potassium iodide. 

The solubility of ammonium bromide in water has been measured by J. M. Eder,6 and by A. Smith and H. E. Eastlack—the values of the latter are, in grms. of salt per 100 grms. of water ... 

Table 133 Relative Nucleo-philicities of Some Important Environmental Nucleophiles n- Values Determined from the Reaction with Methyl Bromide or n-Hexyl Bromide in Water (Eq. 13-3, s = 1)...

Rates of Hydrolysis of Alkyl Bromides in Water at 50° Relative to Ethyl Bromide... 

Reactivities of Various Nucleophiles toward Methyl Bromide in Water at 50°... 

The combination of iodosobenzene 5 and potassium bromide in water generates a powerful oxidant for the oxidation of alcohols. Primary alcohols are converted exclusively to the carboxylic acids in very high yields, whereas secondary alcohols lead to the corresponding ketones, Scheme 13 [73]. 

Bromide in water may be analyzed by one of the following three methods ... 

Haight, G.P. (1951) Solubility of methyl bromide in water and in some fruit juices. Ind. Eng. Chem. 43, 1827-1828. 

Cetyltrimethylammonium chromate, n-C 6H, NH(CH,),CrO, (l). This oxidant is obtained as a yellow-orange solid by reaction of CrO, with cetyltrimethylammon-lum bromide in water at 25°. It can be used to oxidize alcohols to aldehydes or... 

Summary bromine is readily prepared by bubbling chlorine gas into a solution of sodium or potassium bromide in water. The reaction is very mild, and liquid bromine is steadily evolved, forming at first, a deep red liquid that gives off red fumes. The bromine vapors are carried over and condense into liquid bromine. 

Cyanogen Bromide TS Dissolve 5 g of cyanogen bromide in water to make 50 mL. 

The solubility of ferrous bromide in water is given as follows — 5... 

Table III. Comparison of the Values of the Pitzer Interaction Parameters 0 and for HCl -f- NH4Cl, HBr + NH Br, and HBr + Various Substituted Tetraalkylammonium Bromides in Water at 25°C...

Azatryptamine and 2-methyl-7-azatryptamine were refluxed with ethylisothiuronium bromide in water to give the corresponding guanidines. ... 

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