Cyclo hexylamine

Compare the calcu-lated charge on vE/ nitrogen in cyclo-hexylamine and aniline on Learning By Modeling. 

Dicyclohexylammonium nitrite s (DCHN) has a solubility of 3-9g in 100 g of aqueous solution at 25°C, giving a solution pH of about 6-8. Its vapour pressure at 25°C appears to be about 1-3 x 10 N/m but the value for commercial materials depends markedly on purity. It may attack lead, magnesium, copper and their alloys and may discolour some dyes and plastics. Cyclohexylammonium cyclohexyl carbamate (the reaction product of cyclohexylamine and carbon dioxide, usually described as cyclo-hexylamine carbonate or CHC)" is much more volatile than DCHN (vapour pressure 53 N/m at 25°C), and much more soluble in water (55 g in 100cm of solution at 25°C, giving a pH of 10-2). It may attack magnesium, copper, and their alloys, discolour plastics, and attack nitrocellulose and cork. It is said to protect cast iron better than DCHN, and to protect rather better in the presence of moderate concentrations of aggressive salts. 

Ethylene carbonate, reaction with potassium thiocyanate, 42, 59 Ethylene sulfide, 42, S9 Ethyl formate, reaction with cyclo-hexylamine, 41, 14 Ethyl- -hexylamine, 43, 47 5-(2-Ethylhexyl)-l,2,3,4,5-pentachloro-cyclopentadiene, 43, 93 Ethylhydrazinium hydrogen oxalate,... 

Aniline is produced by the hydrogenation of nitrobenzene. A small amount of cyclo-hexylamine is produced as a by-product. The reactions are ... 

Composition, kmol/h aniline 950, cyclo-hexylamine 10, water 1920, hydrogen 5640, nitrobenzene 40, inerts 300. 

Typical feed composition, including impurities and by-products, weight per cent water 23.8, aniline 72.2, nitrobenzene 3.2, cyclo-hexylamine 0.8. 

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. 

In the manufacture of aniline by the hydrogenation of nitrobenzene, the off-gases from the reactor are cooled and the products and unreacted nitrobenzene condensed in a shell and tube exchanger. A typical composition of the condensate is, kmol/h aniline 950, cyclo-hexylamine 10, water 1920, nitrobenzene 40. The gases enter the condenser at 230 °C and leave at 50 °C. The cooling water enters the tubes at 20 °C and leaves at 50 °C. Suggest suitable materials of construction for the shell and the tubes. 

In the production of aniline by the hydrogenation of nitrobenzene, the reactor products are separated from unreacted hydrogen in a condenser. The condensate, which is mainly water and aniline, together with a small amount of unreacted nitrobenzene and cyclo-hexylamine, is fed to a decanter to separate the water and aniline. The separation will not be complete, as aniline is slightly soluble in water, and water in aniline. A typical material balance for the decanter is given below ... 

The aqueous streams from the separators (amine-water) are combined and steam stripped to recover the aniline, the stripped water, containing not more than 30 ppm aniline or 20 ppm cyclo-hexylamine, being discharged to drain. 

Partition of cyclo-hexylamine between aniline and water at 30°C ... 

Equilibrium data for cyclo-hexylamine-water system at 760 mm Hg abs ... 

Aniline present as an impurity in a hydrocarbon stream is to be hydrogenated to cyclo-hexylamine in a trickle bed catalytic reactor operating at 403 K (130°C). 

A. N,N-Dichlorocyclohexylamine Note ). In a 300-ml. threenecked flask fitted with stirrer, addition funnel, thermometer, and calcium chloride tube are placed 9.92 g. (0.10 mole) of cyclo-hexylamine (Note 2) and 50 ml. of dry benzene (Note 3), and the mixture is cooled to 0-5° by an ice bath. A solution of 24 g. (0.22... 

Afanasev et al. [140] have analyzed the literature data concerning adsorption of N-derivatives of morpholine and cyclo-hexylamine at the uncharged mercury electrode. They have also determined free energy of adsorption intrinsic to the interactions of organic molecules with mercury. 

A 1,4-addition mechanism was postulated50 for the addition of cyclo-hexylamine to 72b in the presence of nitromethane. An intramolecular elimination of bromine afforded the (unisolated) epimino-ketonucleo-side 100, which underwent further attack by nitromethane, to give 7-(3,4-cyclohexylamino-3,4-dideoxy-2-C-nitromethyl-a-L-allopyrano-syl)theophyl ine (101). 

I Casals, M Reixach, J Amat, M Fuentes, L Serra-Majem. Quantification of cyclamate and cyclo-hexylamine in urine samples using high-performance liquid chromatography with trinitrobenzenesul-fonic acid pre-column derivatization. J Chromatogr A 750(1-2) 397-402, 1996. 

Further experiments designed to elucidate acid-base relationships among weak acids have been carried out more recently by Streitwieser and his coworkers.50 They studied the equilibrium shown in Equation 3.44, with cyclo-hexylamine as solvent and lithium or cesium cyclohexylamide as base. Using spectrophotometric methods to evaluate the position of the equilibrium, they were able to find relative pKa values for a number of hydrocarbons in which the conjugate base is, in most cases, a conjugated aromatic anion. In order to attach... 

Abraham and Hill22 suggested that the mechanism of acidolysis was that of SE2(cyclic), in which electrophilic attack at the carbon atom undergoing substitution was an important feature the reactivity sequence p-toluidine > cyclo-hexylamine is that of acid strength. A transition state such as (IV) is thus indicated. 

This compound is a secondary amine it bears an allyl substituent on the nitrogen of cyclo-hexylamine. 

The effect of /3-methyl groups was investigated only for the cis-a-arylsulphonyl-j3-bromo- or /3-chloro-ethylenes. The 2-4- to 3-9-fold rate decrease with MeO- ion, as well as the 1-3- to 3-2-fold decrease for /3-bromo-a-p-nitrobenzenesulphonylethylene-di-n-butylamine and cyclo-hexylamine reactions, may point to a contribution of the elimination-addition route with these nucleophiles. When the elimination becomes more difficult, either for thep-methyl derivative or with a chlorine leaving group, a j8-methyl group decreases the substitution rate 20- to 84-fold with the same amines. With PhS- ion, for which other substitution routes are less probable, the rate retardation is higher (322- to 3100-fold). 

Fig. 6.39. Acylation of cyclo-hexylamine with dimethyl carbonate—a possibility for synthesizing the DCC precursor dicyclohexylurea.

Molar Ratio of NH3 to Ketone Cyclo- hexylamine Dicyclo- hexylamine Cyclo- hexanol... 

The decomposition or retro aldol condensation of 2-nitro alcohols, as described in Scheme 9.2, has often been observed in the hydrogenation over Raney Ni in neutral or basic medium. The hydrogenation of (1-nitro-l-cyclohexyl)(4-pyridyl)methanol (7) over Raney Ni in ethanol gave a mixture of 4-hydroxymethylpyridine and cyclo-hexylamine in 73% yield, although 2-nitro-l-(4-pyridyl)ethanol (8) gave the undecomposed amino alcohol in 70% yield (Scheme 9.3).15 The presence of carbon... 

Mangan Acetyl-(N-methyl-cyclo-hexylamin)-tetracarbonyl-XI11/9a, 74... 

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