Cyclohexylamine, 1-methyl

Cycloahphatics capable of tertiary carbocation formation are candidates for nucleophilic addition of nitriles. HCN in strong sulfuric acid transforms 1-methyl-1-cyclohexanol to 1-methyl-1-cyclohexylamine through the formamide (47). The terpenes pinene (14) [2437-95-8] and limonene [5989-27-5] (15) each undergo a double addition of HCN to provide, after hydrolysis, the cycloahphatic diamine 1,8-menthanediamine (16) (48). 

Chemical Name S-Amino-G -dibromo-N-cyclohexyl-N-methyl-benzenemethanamine Common Name N-(2-Amino-3 -dibromoben2yl)-N-methyl-cyclohexylamine Structural Formula ... 

Various amines find application for pH control. The most commonly used are ammonia, morpholine, cyclohexylamine, and, more recently AMP (2-amino-2-methyl-l-propanol). The amount of each needed to produce a given pH depends upon the basicity constant, and values of this are given in Table 17.4. The volatility also influences their utility and their selection for any particular application. Like other substances, amines tend towards equilibrium concentrations in each phase of the steam/water mixture, the equilibrium being temperature dependent. Values of the distribution coefficient, Kp, are also given in Table 17.4. These factors need to be taken into account when estimating the pH attainable at any given point in a circuit so as to provide appropriate protection for each location. 

For example, isobutanolamine (IBA, 2-amino, 3-methyl, 1-propanol, AMP) forms a carbonate (IBA carbonate) that is soluble to the extent of 38% w/w at 25 °C, whereas cyclohexylamine carbonate is only soluble to the extent of 10.5% at 25 °C. This difference in solubility and lack of any significant carbonate stability may result in the fouling of steam traps at the end of long runs of condensate line. 

A molecular dissection of the alkaloid vasicine (52) ultimately resulted in the expectorant and mucolytic agent bromhexine (54). The synthesis starts with displacement of halogen on 2-nitrobenzyl-bromide (53) by N-methyl cyclohexylamine, followed by Raney nickel and hydrazine reduction of the nitro group. Bromination in acetic acid then affords bromhexine. 

The hydrogenation of toluene, aniline, /r-toluidine, and 4-tert-butylaniline was examined over catalyst M1273. The reaction profile for the reactions is shown in Figure 2. From this it can be seen that the order of reactivity is aniline > toluene > /Moluidinc > 4-fer f-butylaniline. The hydrogenation products were methylcyclohexane from toluene, cyclohexylamine from aniline, 4-methyl-cyclohexylamine (4-MCYA) from /Holuidine. and 4-feri-butylcyclohexylamine (4-tBuCYA) from 4-tert-butylaniline. At 50 % conversion the cis trans ratio of 4-MCYA was 2, while tBuCYA it was 1.6. 

Fife et al., 1975. The EM is based on an estimated lower limit for the rate of the reaction of cyclohexylamine with p-nitrophenyl N-methyl-N-phenylcarbamate (aniline does not react at all) and requires a long extrapolation from pK, 10.7 to 2.7, using 0 = 0.8... 

Amino substituents in acyclic derivatives have been discussed by Eggert and Djerassi (396), who emphasize structural and conformational effects, whereas Batchelor has investigated SCS(NH2) and nitrogen protonation shifts in methylated cyclohexylamines (424). The, 3C NMR spectra of amino acids have been compared with those of amines and carboxylic acids (425,426). The transmission mechanisms of amino, ammonium, trimethylammonium, acetamido, and di-acetamido groups have been examined by Faure and co-workers (427), the SCSs of nitro groups by Ejchart (400), and those of azido functions in steroids by Lukacs and co-workers (428). 

Further routes of cyclizations have been studied in parallel in the case of cis- and rra/J5-2-hydroxymethyl-l-cyclohexylamine (106) (880PP73). The preparation of thiourea or urea adducts 107 and 108 with phenyl isothiocyanate or phenyl isocyanate proceeds smoothly. The reaction of 107 with methyl iodide and subsequent alkali treatment, by elimination of methyl mercaptan, resulted in the iminooxazine 109 in high yields. The ring closures of both cis and trans thiourea adducts to 1,3-oxazines proceed with retention. Cyclodesulfuration of the adduct 107 by mercury(II) oxide or N,N -dicyclohexylcarbodiimide resulted in the iminooxazine 109, but the yield was low and the purification of the product was cumbersome. The ring closure of 108 with thionyl chloride led to the iminooxazine 109 in only moderate yield. 

Zur N-Methylierung von primaren Aminen laBt sich auch Methyl-trimethoxy-phospho-nium-tetrafluoroborat verwenden2, wie an der Methylierung von Cyclohexylamin zu Cyc-lohexyl-methyl-amin (75%) gezeigt wurde ... 

Reduction of arenes.1 Raney nickel (Mozingo type) in combination with 2-propanol (reflux) effects reduction of aromatic rings in 2-18 hours. Naphthalene is reduced in 18 hours to tetralin (90% yield) and cis- and frans-decalin (10% yield). Anisole is reduced in 110 hours to cyclohexyl methyl ether (90% yield). Nitrobenzene is reduced quickly to aniline and then further to cyclohexylamine and cyclohexylisopropylamine. 

Yakushin and Shatenshtein (1960) and Yakushin et al. (1959) have determined the ratio of the rate constants for tritium and deuterium replacement by protium in ammonia solutions of fluorene and methyl 2-naphthyl ketone at 25°. Yakushin has obtained data for these reactions in anhydrous methylamine. Streitwieser et al. (1960, 1962b) have measured the ratio fcD/ T for the hydrogen exchange of ethylbenzene and toluene catalysed by a solution of lithium cyclohexylamide in cyclohexylamine at 49-9°. 

In initial steps, 2-nitrobenzylbromide and cyclohexylmethylamine are reacted and that initial product reacted with hydrazine to give N-(2-aminobenzyl)-N-methyl-cyclohexylamine. 

A solution of 29.3 g of bromine in 50 cc of glacial acetic acid was slowly added dropwise to a solution of 159 g of N-(2-aminobenzyl)-N-methyl-cyclohexylamine, accompanied by stirring. The glacial acetic acid was decanted from the precipitate formed during the addition of the bromine solution, and the precipitate was thereafter shaken with 200 cc of 2N sodium hydroxide and 600cc of chloroform until all of the solids went into solution. 

The chloroform phase was allowed to separate from the aqueous phase. The chloroform phase was decanted, evaporated to dryness and the residue was dissolved in absolute ether. The resulting solution was found to be a solution of N-(2-amino-3,5-dibromobenzyl)-N-methyl-cyclohexylamine in ethanol. Upon introducing hydrogen chloride into this solution, the hydrochloride of N-(2-amino-3,5-dibromobenzyl)-N-methyl-cyclohexylamine precipitated out. It had a melting point of 232°-235°C (decomposition). 

The Br/ Ci ratios for the cis isomers are very sensitive to the nature of the nucleophile, being 109-185 for MeO-, 18-3-38 for cyclohexylamine and 3-0-4-2 for di-n-butylamine with (11), while derivatives of (12) show ratios over 200 for both amines. These element effects point to the intervention of an additional route, probably a,j8-elimination-addition, which will be discussed in more detail in the following sections. While the j8-methyl group seems to modify the kBljkc ratios, the effect is not mainly steric in origin, since the ratios are similar for the two amines which have different steric requirements. 

System 2. The chromatograms were developed in the first direction with 450 parts of n-butyl alcohol, 50 parts of glacial acetic acid, and 125 parts of HaO, and in the second direction with 2 parts of n-butyl alcohol, 2 parts of methyl ethyl ketone, and 1 part of H20. A shallow dish, containing 4N NH4OH to replace the cyclohexylamine used by Mizell and Simpson (11), was placed in the chromatographic chamber... 

In the reductive alkylation of ammonia with cyclohexanone, Skita and Keil found that, although cyclohexylamine was obtained in 50% yield over a nickel catalyst, over colloidal platinum dicyclohexylamine was produced as the predominant product even in the presence of an excess molar equivalent of ammonia. Steele and Rylander compared the selectivity to primary amine, secondary amine, and alcohol in the reductive alkylation of ammonia with 2- and 4-methylcyclohexanones over 5% Pd-, 5% Rh-, and 5% Ru-on-carbon as catalysts.18 As seen from the results shown in Table 6.2, the formation of secondary amine is greatly depressed by the methyl group at the 2 position. Thus over Pd-C the secondary amine was formed predominantly with cyclohexanone and 4-methylcyclohexanone while the primary amine was produced in 96% selectivity with 2-methylcyclohexanone. Over Ru-C the alcohol was formed quantitatively with 4-methylcyclohexanone without the formation of any amines, whereas with 2-methylcyclohexanone the alcohol was formed only to an extent of 57%, accompanied by the formation of 4 and 39% of the secondary and primary amines, respectively. These results indicate that secondary amine formation is affected by the steric hindrance of the methyl group to a much greater extents than is the formation of the primary amine or the alcohol. The results with Ru-C and Rh-C also indicate... 

The loss of CO from the hexacarbonyl dicobalt fragment is a key step in the mechanism of the reaction (see section 2.2) the majority of additives are employed to affect this stage of the pathway. Other chemical additives include Lewis bases such as //-butyl methyl sulfide and cyclohexylamine, while molecular sieves have also been employed in order to trap CO out of the reaction mixture.13-16... 

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