Cyclohexyl amines

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. 

Amin omethyl-3,5,5-trimethyl cyclohexyl amine (21), commonly called isophoronediamine (IPD) (51), is made by hydrocyanation of (17) (52), (53) followed by transformation of the ketone (19) to an imine (20) by dehydrative condensation of ammonia (54), then concomitant hydrogenation of the imine and nitrile functions at 15—16 MPa (- 2200 psi) system pressure and 120 °C using methanol diluent in addition to YL NH. Integrated imine formation and nitrile reduction by reductive amination of the ketone leads to alcohol by-product. There are two geometric isomers of IPD the major product is ds-(22) [71954-30-5] and the minor, tram-(25) [71954-29-5] (55). 

The polyamide copolymer of dodecanoic acid with methylenedi(cyclohexylamine) (MDCHA, PACM) was sold as continuous filament yam fiber under the tradename QIANA. As late as 1981, over 145,000 t was produced using high percentages, typically 80%, of trans, trans MDCHA isomer. The low melting raffinate coproduct left after t,t isomer separation by fractional crystallisation was phosgenated to produce a Hquid aUphatic diisocyanate marketed by Du Pont as Hylene W. Upon terrnination of their QIANA commitment, Du Pont sold the urethane intermediate product rights to Mobay, who now markets the 20% trans, trans—50% cis, trans—30% cis, cis diisocyanate isomer mixture as Desmodur W. In addition to its use in polyamides and as an isocyanate precursor, methylenedi (cyclohexyl amine) is used directiy as an epoxy curative. The Hquid diamine mixture identified historically as PACM-20 is marketed as AMICURE PACM by Anchor Chemical for performance epoxies. 

Adoc-Cl, aq. NaOH, dioxane, 16% yield for His isolated as the cyclohexyl-amine salt. ... 

Inclusion of a para acetyl group requires a somewhat different approach to the preparation of these compounds. Reaction of the diazonium salt from p-aminoacetophenone with sulfur dioxide affords the sulfonyl chloride, 203 this is then converted to the sulfonamide, 204, Elaboration via the carbamate with cyclohexyl-amine affords acetohexamide (205). ... 

Addition, chloroform, to olefins to form 1,1,3 tnchloroalkanes, 46, 106 chlorosulfonyl isocyanate to isobutylene to give 0-isovaleiolactam-N-sulfonyl chloride, 46, SI cyclohexyl amine to silicon tetraiso-cyanate, 46, 69... 

Trans-l and ds-3-bromoflavanone Ih were synthesized by the use of the v procedure of Bognar et al. (ref. 9). Cyclohexyl amine and N,N-dimethylformamide (DMF) was purified by distillation, potassium nitrate (Reanal) was used as received. 

Kinetic measurements were performed on a Hitachi 150-20 UV/VIS spectrophotometer. Dehydrobrominations were studied in DMF solution using cyclohexyl amine (CHA) as the base. Applied CHA concentrations were 2, 2.5, 3, 3.5, 4 and 5 10 3 mole.dm-3, initial concentration of 1 was 5 10 5 mole.dm-3 in every case (pseudo-first-order conditions). Ionic strength was adjusted to lO l mole.dm 3 with potassium nitrate. Kinetic curves / D(t) / were recorded at fix wavelength, X = 290 ran and the temperature was maintained at 30, 35.5, 40°C. Stock solutions were made daily for la and freshly for every measurement of Ih. The reaction was started by injection of solution of 1 to the thermostated solution of CHA. 

A similar principle of increasing the reactivity of imidazolides was used for the acylation of cyclohexyl amine and amino acids in an aqueous system 11051... 

In the presence of cyclohexyl amine the photolysis of the dienone (58) gives the cyclohexyl amide expected from dienone ring fission and reaction of cyclohexyl amine with the ketene. However, in the presence of weaker nucleophiles the ring opened product is not trapped and instead there is a relatively slow formation of phenols<36,44) ... 

The reduction of hydroxylamine by titanous salts in water produces the free amino radical, a reaction analogous to the formation of triphenylmethyl from the carbinol and a reducing agent.138 The amino radical will attack benzene to give diaminocyclohexadiene and di-(aminocyclohexadienyl) it converts cyclohexene into cyclohexyl-amine.139... 

Angelici and Brink (40) have found that in the reactions of amine with trans-M(CO),(PPhMe2)2+ (M = Mn or Re), the rate of carbamoyl formation follows the order, n-butylamine > cyclohexyl-amine >, isopropylamine > sec-butylamine >> tert-butylamine, implying a strong steric effect in carbamoyl formation. A similar order has been observed in the rate of reaction of organic esters with amines to form amides (41). The data in Table III indicate that a steric effect may be operative in the Ru (CO) /NR3-catalyzed WGSR, since with tertiary amines the rate follows the order, NMeQ > MeNC.H > NEt > NBu0, which does not reflect the basicity of these amines. 

An early example of this strategy is the palladium black catalyzed conversion of (Z)-2-buten-l,4-diol with primary amines (cyclohexyl amine, 2-aminoethanol, -hexyl amine, aniline) at 120 °C to give A-substituted pyrroles in 46-93% yield [119]. Trost extended this animation to the synthesis of a series of AT-benzyl amines 169 from the readily available a-acetoxy-a-vinylketones 168 [120]. This methodology allowed for the facile preparation of pyrrolo-fused steroids. 

In 2008, Chakraborty el al. reported that Michael addition of nitromethane to the sugar olefinic derivative 36 provided the sugar-based (I-nitro acid ester 37 (Scheme 14), which was used as starting material for the preparation of a novel type of cyclohexyl amines.36... 

In our previous papers (refs. 4,5) we described syntheses of VPI-5 using DPA and TBA. Since that time we have been able to crystallize VPI-5 using many other organics such as diisopropylamine, dipentylamine (DPentA), triethanolamine (TEOA), triisopropanolamine (TIPOA), cyclopentyl amine, and cyclohexyl amine at synthesis temperatures from 120 to 150 C. The wide variety of organics able to crystallize VPI-5 suggests further that the organic does not act as a template and from chemical analyses it is clear that it does not act as a space-filler. 

LaNigH /THF/CH H Zugabe des Imins bei — 78G dann 0", 6h daun 20-25°, 13 h Benzyl-cyclohexyl-amin 97 1... 

HSiClj/HjC-CN 0° dann Riickfl., 4 h 2. KOH/H20 0°, Zugabe fiber 2 h dann 20° Benzyl-cyclohexyl-amin 46 3... 

Durch Reaktion von Cyclohexyl-dichlor-boran mit Azido-phenyl-methan, 4-Azido-l-bu-ten bzw. 4-Azido-l-butin und anschlieBende Methanolyse erhalt man Benzyl-cyclohexyl-amin (88%), 4-Cyclohexylamino-l-buten (78%) bzw. 4-Cyclohexylamino-l-butin (80%) (als Hydrochloride)2 ... 

CYCLOHEXYL- AMINE Amlnocydo-hexane, Hexahydroaniline Flammable Liquid, II 2 3 0... 

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