W-Hexylamine

M-Hexyl alcohol has been prepared by the reduction of ethyl caproate by means of sodium and absolute alcohoB alone or in anhydrous ammonia solution by the reduction of -caproamide by means of sodium and absolute alcohol by the reduction of -caproaldehyde by means of sodium amalgam in dilute sulfuric acid and by means of living yeast, It has also been produced by the action of nitrous acid upon w-hexylamine by the action of sodium upon a mixture of ethyl alcohol and M-butyl alcohol ... 

The reactions involving either benzophenone hydrazone or w-hexylamine have been studied by reaction calorimetry. The benzophenone hydrazone reaction presents zero order kinetics, while the hexylamine reaction is first order in the aryl halide and zero order in the amine. Under synthetically relevant conditions, at 90°C, the rate of the hexylamine reaction is about 30-fold higher than the rate of the benzophenone reaction. 

Scheme 26.3 Competitive reaction of benzophenone hydrazone and w-hexylamine.

Numerous studies of the EPR spectra of the Cu(R2 Dtc)2 complexes in the presence of bases have been reported. The interaction of Cu(n-Bu2Dtc)2 with Pip, Py, and w-hexylamine (Hex) was studied by variable-temperature EPR measurements (139). Evidence for the formation of 1 1 adducts was presented and thermodynamic parameters were reported. For the Pip, Hex, and Py adducts, respectively, equilibrium constants of 3.9(1), 2.1(1), and 0.40(2) 1 mole"1 were determined. In the same order, AH0 values of —7.5(4), —7.3(12), —5(2) kcal mole"1 and AS0 values of —22(1), —23(2), and —19(3) eu were reported. The rate of adduct formation is primarily limited by the entropy of activation, while the rate of dissociation is limited by the enthalpy of activation. 

Problem 18.51 Synthesize the following compounds from alcohols of four or fewer C s, cyclohexanol and any needed solvents and inorganic reagents, (a) w-hexylamine, (b) triethylamine N-oxide, (c) 4-(N-methylamino)heptane, (cf) cyclohexyldimethylamine, (e) cyclopentylamine, (/) 6-aminohexanoic acid. ... 

Figure 8.14. GC/MS analysis of amine-pentafluorobenzyl derivatives in a Cabernet Sauvignon wine. Analytical conditions 5% phenyl-95 % dimethlypolysiloxane capillary column (30 m x 0.25 mm, 0.25 pm) oven temperature program 45 °C for 4 min, 15°C/min to 280 °C, isotherm for 15 min. (1) methyl- -amine and methylamine (coeluted), (2) ethylamine, (3) n-propylaminc, (4) w-hexylamine, (5) 2-phenylethylamine, (6) 1,4-diaminobutane, and (7) 1,5-diaminopentane. (Reproduced from Journal of Agricultural and Food Chemistry, 2000, 48, p. 3314, Ngim et al., with permission of American Chemical Society.)...

EMC Corporation have claimed an even wider range of potential thermal stabilisers, including phenyl sulfoxides [71] aliphatic orthosilicates [72] hydroxycarbyltrialkoxysilanes [73] aminobenzophenones [74] stearamide [75] substituted alkane and alcohols such as diphenylmethane or benzylphenylcarbinol [76] disulfides such as phenyldisulfide or hexyldisulfide [77] sulfones such as dihexylsulfone or di-p-tolylsulfone [78] ureas or thioureas [79] amines such as didoceylamine or tri-w-hexylamine [80] and aromatic isocyanates [81]... 

Closer examination of the reaction between w-hexylamine and TaS2 suggested that the increase in intercalation rates was not due to increased mass transport, but to an irreversible change in the host. Electron microscopy clearly shows that the initial effect of sonication is to reduce the size of the solid particles, in this case a reduction from 60-90 pm to 5 pm within the first 15 minutes. Furthermore, the degree of intercalation had almost reached its maximum value at this point, suggesting that this is the major determinant of the reaction time rather than effects related to subsequent surface damage (Plate 3, see p. 16). 

Solubility of cyclo-hexylamine in the water phase 0.12 per cent w/w and in the organic phase 1.0 per cent w/w. 

Diazirines are the cyclic isomers of the alphatic diazo compounds. Both the diaziridines and the diazirines are starting materials for the synthesis of alkyl hydrazines. 3,3-Pentamethyl-enediaziridine can be hydrolyzed quantitatively to hydrazine. Methylamine may be substituted for ammonia in the procedure resulting in l-methyl-3,3-pentamethylenediaziridine (m.p. 35-36°, yield 62% of theoretical) and then methyl hydrazine. Use of ethylenediamine leads to ethylene bis-hydrazine via a bifunctional diaziridine (m.p. 143-144°, yield 48% of theoretical). Ammonia can also be replaced by w-propylamine or cydo-hexylamine cyclohexanone by acetone. 

In sub-FC, a detailed study of the influence of mobile phase additives on the chiral resolution of isoxazoline-based Ilb/IIIb receptor antagonists was carried out by Blackwell [145] on Chiralcel OD-H CSPs. The different mobile phase additives used were acetic acid, trifluoroacetic acid, formic acid, water, triethylamine, triethanolamine, n-hexylamine, trimethyl phosphate, and tri-w-butyl phosphate. In general, n-hexylamine and tri-/ -butyl phosphate mobile phase additives resulted in better resolution. The chiral separation of four 1,3-dioxolane derivatives on an amylose-based column has been described [151]. The effects of mobile phase composition, temperature, and pressure have been investigated. The nature of the modifier is the main parameter it has the highest impact on chiral resolution and is more important than the polarity of the mobile phase. Therefore, the organic modifier that gave the best enantiomeric separation was different for each compound. 

The situation is more complicated for nonspontaneous bimolecular reactions involving a second reactant, whose distribution between the two pseudophases has to be considered. The simplest situation is that for reaction of a hydrophobic species whose solubility in water is sufficiently low that it is incorporated essentially quantitatively in the association colloid. For example, for reactions of nucleophilic amines in aqueous micelles, second-order rate constants in the micellar pseudophase calculated in terms of local concentrations are lower than in water [103,104], because these reactions are inhibited by a decrease in medium polarity and micelle/water interfaces are less polar than bulk water [59,60,99101]. Nonetheless, these bimolecular reactions are generally faster in micellar solutions than in water because the nucleophile is concentrated within the small volume of the micelles. Similar results were obtained for the reaction of 2,4-dinitrochlorobenzene (5) with the cosurfactant -hexylamine in O/W microemulsions with CTABr and w-octane [99], again consistent with the postulated similarities in the interfacial regions of aqueous micelles and O/W microemulsions. 

Besides methanol, many other polar and non-polar modifiers have also been used to successfully improve the separation in SFC. These modifiers include acetone, acetonitrile, acetic acid, butane, butanol, w-butyl chloride, carbon tetrachloride,dioxane, ethanol, formic acid, heptane, hexane, -hexylamine, methylene chloride, nitromethane, propanol, proprionitrile, tetrahydrofiiran, toluene, triethanolamine, trifluoroacetic acid, trifluoroethanol, trimethyl phosphate, and water. 

Reduction of Azide. DBBS very effectively and quantitatively reduces w-hexylazide into /3-hexylamine in 2-3 h in dichlorome-thane (eq 30). ... 

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