Aliphatic cyclic amines

Table 7 Effects of Aliphatic Cyclic Amines on Polymerization...

Recently, two other groups have shown that exocyclic iminium salts can be useful mediators in asymmetric epoxidation. Komatsu has developed a system based on ketiminium salts [14], prepared through the condensation of aliphatic cyclic amines with ketones. A chiral variant was also produced, derived from prolinol and cyclohexanone, which gave 70% yield and 39% ee for cinnamyl alcohol (Scheme 5.7). 

Various other substituted azoles such as pyrazoles, benzimidazoles, and primary and secondary aliphatic cyclic amines were also successfully coupled with chlorobenzenes to afford (V-arylated products in fair yields (Scheme 9, entries 1-10). 

Luminescence has been used in conjunction with flow cells to detect electro-generated intennediates downstream of the electrode. The teclmique lends itself especially to the investigation of photoelectrochemical processes, since it can yield mfonnation about excited states of reactive species and their lifetimes. It has become an attractive detection method for various organic and inorganic compounds, and highly sensitive assays for several clinically important analytes such as oxalate, NADH, amino acids and various aliphatic and cyclic amines have been developed. It has also found use in microelectrode fundamental studies in low-dielectric-constant organic solvents. 

The next seven references are cited not because of the experimental procedures described but because they indicate diversification in the types of enamines prepared and studied. Both Paquette (25) and Kasper 26) have condensed 2,5-methylene-l,2,5,6-tetrahydrobenzaldehyde (5-nor-bornene-2-carboxyaldehyde) (2) with several cyclic and open-chain aliphatic secondary amines. Kasper studied the ratio of endo to exo aldehyde formed upon hydrolysis of these enamines and the dihydro enamines. Paquette investigated the addition of sulfene to the enamines. -Fluoro-... 

Besides aromatic tertiary amines, the aliphatic cyclic tertiary amines such as N-methyl(or ethyl) morpholine can also be used in coupling with BPO to enhance the Rp of MMA polymerization [20], Since the... 

For aliphatic monoamine [43], it is shown that secondary amines R2NH always possess a higher promoting effect for the polymerization of AAM and even the primary amine PA will enhance the polymerization with Rr = 1.47 and Ea = 36.4 kJ/mol, while the tertiary aliphatic amine TPA will not provide the polymerization due to some steric hindrance (Table 6). All of the data of cyclic amines listed in Table 7 are effective, i.e., NMMP with Rr = 1.81 and Ea = 29.9 kJ/mol showing the absence of steric hindrance. 

In this study we examine the generalities in reductive alkylation however, since the subject is vast, we limited ourselves to the interaction of aromatic and aliphatic primary amines and diamines with ketones. The ketones examined include the cyclic ketone, cyclohexanone, and aliphatic ketones such as acetone, and methyl isobutyl ketone (MIBK). We limited our study to sulfided and unsulfided Pt and Pd catalysts supported on activated carbon that were commercially available from Evonik Degussa Corporation. 

Oxidative attack on a carbon-hydrogen bond of an alkyl group a to a nitrogen atom is not restricted to saturated aliphatic amines. In fact X in an X-N-CH- structural subunit can be virtually any common atomic grouping that can be found in stable organic molecules. For example, w-carbon hydrogens of Aralkyl-substituted aromatic cyclic amines (119), aryl amines (120), amides (121), amidines (122), A-nitrosodialkylamines (123), etc. are all subject to oxidative attack, carbinolamine formation, and in most cases release of an aldehyde or ketone depending on the substitution pattern (1° or 2°)... 

Dimethyl N.N-disubstituted aminomethylenemalonates (291) were prepared in 35-82% yields by the addition of dimethyl chloromethylenemalo-nate (287, X = Cl) in diethyl ether to an ethereal solution of secondary aliphatic or cyclic amines in the presence of triethylamine at 0-5°C, after which the reaction mixtures were stirred at ambient temperature (78T2315). 

Quinine has two potentially basic centres, a cyclic tertiary amine at a ring junction, and one in a quinoline ring system. pAfa 8.5 is reasonably basic, and this is most likely from the aliphatic tertiary amine. We need to convince ourselves that the quinoline nitrogen is less basic. This is true. As far as reactivity is concerned, a quinoline ring system behaves as two separate parts, either pyridine or benzene, depending upon the reagent. Thus, quinoline has pATa very similar to that of pyridine, i.e. around 5. 

J. R. Malpass, in Comprehensive Organic Chemistry (D. Barton, D. Ollis, eds.), Vol. 2, p. 3-59, Pergamon Press, Oxford 1979 . .Aliphatic, Acyclic, and Cyclic Amines". 

A related oxycarbonylation of secondary amines to A/ JV-disubstituted ureas in the presence of copper(I) salts at room temperature and atmospheric pressure has been disclosed by Brackman.6263 The reaction is particularly effective with cyclic secondary amines such as piperidine and morpholine (equation 293), with primary and aliphatic secondary amines being much less reactive.6263... 

Hardly detectable in case of acyclic aliphatic amines high intensity for aromatic and cyclic amines... 

Polycyclic aromatic nitrogen compounds, such as quinoline, indole, acridine, and carbazole, are the main nitrogen-containing compounds in oil fractions, and monocyclic pyridine and pyrrole as well as anilines are present in coal tar (Scheme 11). Saturated cyclic amines are found as products of ring hydrogenation of the compounds shown in Scheme 11 after HDN. Aliphatic amines are rarely found in fuels and only in low concentrations after HDN since their nitrogen atoms are easily removed. 

Aliphatic and cyclic amine NH protons absorb from S 3.0 to 0.5 aromatic amines absorb from S 5.0 to 3.0 in CDC13 (see Appendix E) because amines are subject to hydrogen bonding, the shift depends on concentration, solvent, and temperature. Amide, pyrrole, and indole NH groups absorb from 8 8.5 to 5.0 the effect on the absorption position of concentration, solvent, and temperature is generally smaller than in the case of amines. The nonequivalence of the protons on the nitrogen atom of a primary amide and of the methyl groups of N, /V-dimethylamides is caused by... 

Answer Xl-g is an aliphatic cyclic tertiary amine (a-pyrro-lidino-m-nitroethy (benzene). 

Lewis and his coworkers reported the intramolecular photoaddition of aliphatic secondary amines to arylalkenes to give 5- and 6- membered cyclic amines (Scheme 17) [66-67]. Ohashi reported that the other type of photoaddition reaction takes place when 1,4-dicyanobenzene and triethylamine are used as substrates. This photoreaction can be explained in terms of the deamination of the initially produced diethylaminoethylated compound (Scheme 18) [68]. 

The molecular-ion peak M is weak to absent in high-molecular weight aliphatic open-chain amines, but strong in aromatic and cyclic amines. 

Carboxylic and sulfonic acid groups import acidity to organic compounds. Most carboxylic acids and sulfuric acids are readily dissolved in water, and their titration with a base is straightforward. If solubility in water is not sufficient, the acid can be dissolved in ethanol and titrated with aqueous base. Aliphatic amines and many saturated cyclic amines can be titrated directly with a solution of a strong acid. Esters are determined by saponification with a measured quantity of standard base. The excess base is titrated with standard acid. 

Other primary or secondary, aliphatic or cyclic amines may be used with similar results. 

Intramolecular displacement of aliphatic amines having a suitable leaving group also affords cyclic amines. In order to avoid further alkylation, the amino function is protected by appropriate groups. The tosyl group has frequently been utilized to this end, where cyclization proceeds through an anionic displacement reaction. 

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