Aliphatic amine residue

The modified procedure involves refluxing the N-substituted phthaUmide in alcohol with an equivalent quantity of hydrazine hydrate, followed by removal of the alcohol and heating the residue with hydrochloric acid on a steam bath the phthalyl hydtazide produced is filtered off, leaving the amine hydrochloride in solution. The Gabriel synthesis has been employed in the preparation of a wide variety of amino compounds, including aliphatic amines and amino acids it provides an unequivocal synthesis of a pure primary amine. 

While aromatic nitro and azoxy compounds have been reduced to azo compounds with lithium aluminum hydride, aliphatic nitro compounds produced only the corresponding aliphatic amines [65]. The usual technique involves dropwise addition of 1 mole of nitro compound in ether to 1.05-1.15 moles of lithium aluminum hydride in ether solution at Dry Ice temperatures followed by warming to room temperature. If the resulting product is only slightly soluble in ether, hydrolysis should be carried out with dilute sulfuric acid. Then the azo compound simply needs to be filtered off, washed with water, and dried. If the product is ether-soluble, the ether layer is separated, evaporated, and the residue is recrystallized [65, 66]. 

As was mentioned earlier, polyethylenimine has many amine nitrogens in it, and these have the potential to act as nucleophiles (e.g., in an aminolysis reaction). In addition, they are locally concentrated (Figs. 2 and 3). Furthermore, polymers with attached aliphatic acyl groups provide apolar binding sites in proximity to amine residues of the polymer. One might expect, therefore, to find progressively enhanced rates of... 

A reconstructed ion chromatogram (GC-MS) containing extractable contaminants isolated from a typical lot of foam is shown in Figure 4. The qualitative composition of the extractable contaminants was provided by GC-MS. Contaminant profiles were identical for each of the two solvent systems employed, methylene chloride (1003 ) and ethyl ether/hexane (5/95). The contaminant chemistry shown here and again in Figure 5 in several instances is consistent with the manufacturing process data shown in the box, most notably the presence of residual toluene diisocyanate (starting materials, see Scheme II) and an aliphatic amine (possible reaction catalyst). 

Reinhoudt et al. have chosen tetraether derivatives of calix[4]arenes fixed in the cone-conformation as such a molecular skeleton.280 Bis-melamine derivatives 135 are easily prepared in a huge diversity (different residues Y, R1, R2) from 1,3-diamino calix[4]arenes by reaction with cyanurchloride, followed by stepwise substitution of the remaining chlorine atoms by ammonia and an aliphatic amine. 

Anodic oxidation of primary and tertiary [193] aliphatic amines in acetonitrile containing a small amount of residual water produced several compounds, including aldehydes. Tripropylamine is oxidized according to Eq. (51) ... 

The diazonium salt is readily prepared from the aminophenyl group, but does not result from treatment of an aliphatic amine (such as the APTES-derivatized surface) with nitrous acid. The activated surface is now ready for enzyme coupling, since diazonium salts are very reactive toward protein tyrosine residues (Eq. 4.4) ... 

A-(6-Chloronaphthalen-2-)sulfonylpiperazine derivatives 4 and 5 (Figure 15.12) are potent factor Xa inhibitors. Haginoya et al proposed to replace the pyridine-phenyl or the pyridine-piperidine residue by a fused-bicyclic ring which contains an aliphatic amine and a pyridine to yield the compound 6 that has an interesting factor Xa inhibitor activity. The bioisosteric replacement of the pyridine moiety of the 6-methyl-5,6,7,8-tetrahydro-[l,6]naphthyridine by phenyl, thiophene, or thiazole analogs yielded analogs with similar or better antifactor Xa activity, but also to conserve a moderate bioavailability. 

For the 1SN isotropic chemical shift the protonation-induced shifts are of the order of 100 ppm towards lower frequencies for aromatic amines, and about 25 ppm towards higher frequencies for aliphatic amines [62]. For example, in the case of glycine residues in solid oligopeptides, a relationship between the N-O distance and the 15N chemical shift tensor in C=0 H-N hydrogen bonds has been proposed [63]. 

Methylation of aliphatic amines to tertiary amines 1015 1 mole of a primary amine is added with cooling to a mixture of 5 moles of 90 % formic acid and 2.2 moles of 35 % formaldehyde solution. Secondary amines require only half of these amounts of formic acid and formaldehyde, but an excess is not disadvantageous. Reaction begins when the mixture is heated on a steam-bath. When the initial vigorous evolution of carbon dioxide ceases, the mixture must be heated for a further 2-4 h, in all for 8-12 h. Then somewhat more than 1 mole of hydrochloric acid is added and the formic acid and formaldehyde are distilled off. The colorless residue is dissolved in water and basified with 25 % sodium hydroxide solution, and the amine is distilled off in steam. The distillate is saturated with solid potassium hydroxide, and the oil that separates is dried over potassium hydroxide and distilled from sodium. The following tertiary amines were thus obtained in more than 80% yield iV,iV-dimethylbutyl-amine, b.p. 94° A TV-dimethylbenzylamine, b.p. 176-180° and 1-methylpiperidine, b.p. 106°. 

Reaction with carbodiimides 805 A primary aliphatic amine (0.1 mole) is added to a solution of dicyclohexylcarbodiimide (0.1 mole) and carbon disulfide (40 ml) in ether or tetrahydrofuran (100-200 ml) stirred at —10°. The temperature is allowed to rise to 20° during 3 h. The mixture is then set aside at room temperature for 12 h, after which the di-cyclohexylurea, is filtered off and washed with a little ether, the filtrate is evaporated, and the residual isothiocyanate is distilled in a vacuum or recrystallized. Yields are about 80%. 

The last section shows the effect of substituents (Rj, R2) on the aliphatic amide moiety. As for the aliphatic side chain, it was found that the alpha-branched alkyl side chain was essential for stabilizing the diamide structure. In the case of non-branched alkyl, the diamide derivatives tend to decompose to the corresponding phfhalimides. A variety of substituents were examined to improve the activity. As shown in Table I, the introduction of a heteroatom or a functional group increased the insecticidal activity especially a sulfur atom within the alkyl side chain markedly increased the activity. This sulfonylalkylamine is also novel as an amine residue in pesticide chemistry. In summary, flubendiamide has unique substituents as essential parts of the structure in three adjacent positions on the benzene ring, which characterizes the chemical structare of flubendiamide as totally novel. 

Michael-type addition of secondary aliphatic amines to the conjugated double bond of the dehydroproline residue afforded 26-dialkylamino derivatives of pristinamycin (88), but only in low yields [130]. 

When detection is based on the oxidation of a tertiary aliphatic amine, for example, proper pH is essential. Ideally, the nitrogen atom should not be protonated, since the lone pair of electrons is involved in the oxidation process (Schwartz and David 1985). In addition, an unprotonated nitrogen is less reactive towards residual silanol groups on the reversed-phase column, which then improves the peak shape (so-called ion suppression). In order to keep the nitrogen unprotonated, the pH of the mobile phase should be over the pKa value of the amine. However, the pKa in eluents containing organic solvents may not always be equivalent to values determined from pure aqueous solutions. Also, the pH must not be higher than necessary, since it does not further the amine s oxidation, but instead promotes the oxidation of water. The choice of pH should always be determined experimentally. One should also consider the stability of the column. Often one must make some compromise between separation and detection. 

Organic residual components are the most worrying because of their toxicity. Some of these compounds are formed as by-products. Volatile organic compounds are determined by headspace GC, GC-MS. Intermediate products, such as sultones and sulfones, from sulfonation of olefin and alkyl-benzene, respectively, can be detected by LC. Unreacted products, like ethylene oxide from the synthesis of ethoxylated nonionic and anionic surfactants, are studied by GC benzyl chloride from the quaternization of tertiary amines and aliphatic amines from amidation reaction are determined by LC (Figure 5). 

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