N-Octyl bromide

Alkylation of several substituted benzoic acid salts with n-octyl bromide was performed under solvent-free PTC with excellent yields (95 %) within a very short reaction time [93] (2-7 min). Oil bath heating (A) led to yields equivalent to those produced under the action of microwave irradiation, which thus revealed only thermal effects in the range of temperature used (145-202 °C) (Eq. 39). 

Conversely, when n-octyl bromide was used with the less reactive terephthalate species, which constitutes a slow-reacting system , the yield was raised from 20 to 84% under the action of microwaves compared with A, which can be attributed to a later TS along the reaction coordinates (Eq. 40). 

The synthesis of octylthiocyanate by reaction of n-octyl bromide with KSCN, and its subsequent isomerization to isothiocyanate, have been realized by use of TBAB under the action of MW irradiation. The effect of inorganic solid supports was studied (Si02, K10, graphite, NaCl) (Eq. 64). 

A detailed study of the formation of n-octyl ethers under solidrliquid two-phase conditions in the absence of an added solvent has been reported [10], Potassium alkoxides tend to produce higher yields of the ethers than do the corresponding sodium derivatives, but octene is the major product in the reaction of 1-bromooctane with potassium t-butoxide. High temperatures also tend to promote the preferential formation of octene and slightly higher yields of the ethers are obtained using n-octyl tosylate in preference to n-octyl bromide. p-Fluorinated acetals have been prepared either under basic catalytic liquidrliquid or solidrliquid conditions from the fluori-nated alcohol and dichloromethane [11] with displacement of the fluorine atoms. 

To 10 mmoles of potassium carboxylate were added in a Pyrex flask 10 mmol of n-octyl bromide and 1 mmol of tetraalkylammonium salt (Aliquat 336 or Bu4NBr). After shaking, the flask was introduced in the microwave oven (or in an oil bath for control experiments) for the indicated time. The temperature was measured by introducing a Quick digital thermometer in the sample just at the end of each irradiation. Organic products were recovered by a simple elution with 50 mL diethyl ether or methylene chloride and subsequent filtration over... 

Montanari and co-workers7 used polypode ligands (9) as phase-transfer catalysts. Thus, a saturated aqueous solution of K.I was stirred with n-octyl bromide in the presence of a multi-armed ligand the resulting production of n-octyl iodide was followed by gas chromatography. Catalyst activity was found to vary with the hydro-phobicity of the arms. When the chains are terminated by butyl groups, 72 hours... 

Yoon and Kim have prepared potassium triphenylborohydride (KPhjBH) and examined the reducing ability toward alkyl halides. n-Octyl iodide is reduced within 1 h at 0 °C, whereas n-octyl bromide takes 24 h for complete reduction. Secondary bromides are inert under these conditions. 

This procedure illustrates a process which is general for 1,1-diphenyl substituted hydrocarbons. Diphenylmethane has been alkylated with benzyl chloride, benzhydryl chloride, a-phenyl-ethyl chloride, /3-phenylethyl chloride, isopropyl chloride, 2-ethylbutyl bromide, and n-octyl bromide in yields of 99, 96, 97, 88, 86, 96, and 99%, respectively. 

Distributions of relaxation times produce shapes similar to the broken lines in Figs. 2-6 (a) and (b). The curves labeled I result from a broad distribution, and those labeled II from mixtures of more or less discrete relaxation times. Type II curves are found less often than type I. The best known examples of type II are in alcohols, but the interpretation does not necessarily involve H bond rearrangements. Aspherical molecules, for example, may show a range of relaxation times and give curves of type I. This is true for n-octyl bromide (1906, pp. 58, 104). 

Absolute rate constants were first measured by the rotating sector ESR technique59-60 and supplemented by competition experiments to give further relative values 56-61-63 for example, for the B113S11 radical at 298 K, fc(CH2=CHCH2Br)/fc(BuBr) = 30.5. n-Octyl bromide and 4-t-butylbromobenzene are commonly used as standards. 

Figure 4.23 Oxygen-car7ing capacity of human blood in comparison with pure perfluoro-n-octyl bromide (PFOB) and the blood substitute Fluosol [105] (graph modified from Ref. [102]).

PFOB perfluoro-n-octyl bromide TEMPO 2,2,6,6 -tetramethylpiperidine- N-... 

The alkylation of potassium benzoate with n-octyl bromide under classical solid-liquid PTC (crown ether, chloroform) leads to only 58 % of n-octyl ester after 40 h at 85 °C. Under solvent-free conditions (2% of Aliquat), yield is quasi-quantitative (95%) within 2 h at the same temperature [Eq. (47)] [81]. 

Cross-coupled products are formed in insignificant amounts if sec- or tert-alkyllithiums are employed. However, if 1-bromonaphthalene is treated first with jec-butyllithium and then with n-octyl bromide, 1-n-octylnaphthalene can be obtained in 74% yield. ... 

Subsequent reactions with n-octyl bromide, c-hexyl bromide, bromoacetaldehyde diethylacetal, benzyl chloride, oxirane, carbon dioxide, carbon disulfide (followed by reaction with methyl iodide), and methyl isothiocyanate. 

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