Cyclohexylamine from cyclohexanone

Therefore, CL and die depolymerized product from which CL is regenerated contain various impurities which are present in widely fluctuating amounts depending on the reclamation processes involved. In particular, the presence of cyclohexanone, cyclohexanone oxime, octahydrophenazine, aniline, and other easily oxidized compounds affects die permanganate number. Also volatile substances such as aniline, cyclohexylamine, cyclohexanol, cyclohexanone, nitrocy-clohexanone, and aliphatic amines may also be present in the CL.22... 

Notwithstanding, conformational factors apparently play a part in the enamine-imine equilibrium of the SchifF base prepared from cyclohexanone and cyclohexylamine, as shown by their infrared spectra 28 the base appears to be a mixture of both tautomeric forms, N-cyclo-hexylidenecyclohexylamine and N-1 -cyclohexenyIcyclohexylamine. Replacement of the cyclohexyl group by a phenyl group appears to stabilize the imino form.24... 

Aza-enolate alkylation is so successful that it has been extended from aldehydes, where it is essential, to ketones where it can be a useful option. Cyclohexanones are among the most electrophilic simple ketones and can suffer from undesirable side-reactions. The imine from cyclohexanone and cyclohexylamine can be deprotonated with LDA to give a lithium aza-enolate. In this example, iodomethylstannane was the alkylating agent, giving the tin-containing ketone after hydrolysis. 

In competition with these amination reactions, intramolecular aminations can occur, and they become the main reaction in certain cases. The oxaz-iridine 61, derived from cyclohexanone, reacts with methoxide to give the phenylhydrazine carboxylic ester, and with cyclohexylamine to the sub-... 

Secondary1005,1031-1033 and tertiary amines1021,1029 1033-1035 are obtained analogously from ketones, by using the amine formate or jV-alkyl- or N,N-dialkyl-formamide in place of ammonia (or ammonium formate) or formamide. In this way iV-methyl- and iV,iV-dimethyl-cyclohexylamine are obtained from cyclohexanone and formic acid by methyl- and dimethyl-formamide, respectively, whereas formamide and formic acid give cyclohexylamine.1033... 

The analogous fragmentation from cyclohexylamine and cyclohexanone leads to ions at mh 56 and miz 55, respectively. 

Reductive amination of cyclohexanone using primary and secondary aHphatic amines provides A/-alkylated cyclohexylamines. Dehydration to imine for the primary amines, to endocycHc enamine for the secondary amines is usually performed in situ prior to hydrogenation in batch processing. Alternatively, reduction of the /V-a1ky1ani1ines may be performed, as for /V,/V-dimethy1 cyclohexyl amine from /V, /V- di m e th y1 a n i1 i n e [121 -69-7] (12,13). One-step routes from phenol and the alkylamine (14) have also been practiced. 

Following the logic of the deuterium labeling, regioisomers of cyclohexanones, cyclohexylamines, cyclohexylalcohols and others can be identified by strict application of the above mechanism. Regardless of some limitations of the method, e.g., that it is impossible to distinguish a 2,3-dimethyl from a 2-ethyl or 3-ethyl derivative, the method provides a valuable aid in structure elucidation. 

An example of the simplicity and potential of the photo-oxygenation reaction is described for the preparation of (Z)-l-hydroperoxy-A-[(Z)-3-methoxycarbonyl)-2-propenylidene]cyclohexylamine A-oxide (P) starting from 2-methoxyfuran and cyclohexanone oxime, which both can be purchased and used without further purification. 

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... 

Acetone is readily converted to isopropylamines in the vapor phase under conditions that apply for the lower (Cj-C ) aldehydes. The preparation of 2-aminobutane from methylethyl ketone (butanone-2) is satisfactorily carried out in the liquid phase, preferably in the presence of butanol-2 since the latter can also be converted to amine by ammonolysis. The intranuclear ketone cyclohexanone can be converted to cyclohexylamine by hydroammonolysis in the vapor phase. The preparation of 12-amino-stearamide from the corresponding keto acid is, however, best carried out in the liquid phase. The pertinent reactions are ... 

A soln. of p-methylbenzyl alcohol in ethyl acetate stirred 0.5 hr. at room temp, with excess aq. 10%-NaCl (commercial bleach) in the presence of ca. 5% tetrabutylammonium hydrogen sulfate as phase transfer catalyst p-tolualdehyde. Y ca. 100%. - Similarly Cyclohexylamine, after hydrolysis of the intermediate N-chlorimine with dil. mineral acid -> cyclohexanone. Y 98%. F. e., also nitriles from prim, amines, and limitations, s. G. A. Lee and H. H. Freedman, Tetrah. Let. 1976, 1641. 

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