Amines, acetylation tertiary

The quinaldine is separated from any unreacted aniline and from the alkyl-anilines by treatment with acetic anhydride, basified with sodium carbonate and steam distilled. Only the primary and secondary amines are acetylated the acetylated amines are now much less volatile so that separation from the steam-volatile quinaldine (a tertiary amine) is facile. 

Acetyl chloride reacts immediately and often violently with primary and secondary amines, but not with tertiary amines, for example ... 

Acetoiicetyliition Reactions. The best known and commercially most important reaction of diketene is the aceto acetylation of nucleophiles to give derivatives of acetoacetic acid (Fig. 2) (1,5,6). A wide variety of substances with acidic hydrogens can be acetoacetylated. This includes alcohols, amines, phenols, thiols, carboxyHc acids, amides, ureas, thioureas, urethanes, and sulfonamides. Where more than one functional group is present, ring closure often follows aceto acetylation, giving access to a variety of heterocycHc compounds. These reactions often require catalysts in the form of tertiary amines, acids, and mercury salts. Acetoacetate esters and acetoacetamides are the most important industrial intermediates prepared from diketene. 

The present authors have found that the preparation of 7V-acetyl aziridine derivates provides the most secure method of differentiating aziridines from primary amines which are alternate reaction products in a number of cases. The infrared spectra of the former derivatives show only a peak at 1690 cm" for a tertiary amide peaks at ca. 3440 and 1530 cm" indicative of a secondary amide are absent. Acetylation also shifts the aziridine ring protons to a lower field in the NMR by ca. 1 ppm relative to the parent aziridine. The A"-acetyl aziridines are hydrolyzed with 3% methanolic potassium hydroxide. " Published NMR spectra of several 16j5,17j -aziridines reveal resonance patterns resembling those of the respective epoxides. " ... 

The seco amide alkaloids have been subjected to various transformations, mainly for structure elucidation purposes. When treated with lithium aluminium hydride, arnottianamide (206) was converted to the tertiary amine, deoxyarnottianamide (224), which on methylation with the Rodionow reagent gave deoxy-O-methylarnottianamide (225) (172,175). Arnottianamide (206) could be O-acetylated (174) as well as O-methylated with diazomethane in HMPA (172). Isoarnottianamide (208) was O-methylated to trimethoxy derivative 226, which under Bischler-Napieralski conditions recyclized to the benzophenantridine alkaloid, chelilutine (227) (176) (Scheme 33). 

The reaction of tertiary amines such as trimethylamine or triethylamine, with acetyl or benzoyl chloride, followed by anion exchange with sodium tetraphenylborate gives stable... 

Reaction of 1-nitropropane with glutaraldehyde in aqueous ethanol in the presence of sodium hydroxide yields a mixture of two products, the major component of which, lr-ethyl-l-nitrocyclohexane-2c,6f-diol (98), can be isolated in 36% yield ). Acid-catalyzed acetylation converts (98) into the di-O-acetate, hydrogenation yields the corresponding amine, which has been characterized as the hydroacetate, N-acetate and triacetate. Configurational assignments followed from NMR data, which clearly showed the steric non-equivalence of the two hydroxyl groups vicinal to the tertiary center. 

IV-acetyl pyrrolidines and -piperidines to the corresponding diones or ketones were similarly effected [405, 406], as were conversions of diacetyl and dibenzyl piperazines to diketo componnds by the same system (Table 5.1) [407]. Methylene groups adjacent to the N atom in tertiary polycyclic amines were oxidised by RuO /aq. NaCIO j/CCl (Fig. 5.5) [408]. A large-scale oxidation of l,4-bis(2-phenylethyl) piperazine to the dione was made by RnO /aq. Na(10 )/Et0Ac [409], and RuO /aq. Na(IO )/CCl converted dialkyl or diaryl A A -dimethyladenosines to the corresponding monoamido derivatives (Fig. 5.4) [410]. 

Several oxidations of amines involved oxidation of methyl groups adjacent to tertiary amines to carbonyl groups. Oxidation by RuO /aq. Na(IO )/CCl of 2, 3, 5 -tri-0-acetyl- or -benzoyl derivatives of A A -dimethyladenosine, A, A -... 

One of the more common pathways for the metabolic transformation of tertiary amines involves A -dealkylation to a secondary amine. The observation that those products often show the same biological activity as the parent dmg in many cases confounds the issue of the identity of the chemical species responsible for the drug s action. The fact that the dealkylation product of disobutamide shows antiarrhythmic activity in its own right prompted the synthesis of the acetyl derivative of that secondary amine this agent may be considered a latent form of the active metabohte. This compound is prepared by first repeating the penultimate step in the disobutamide synthesis using (Af-benzyl-Af-isopropyl)-2-chloroethylamine instead of the diisopropyl intermediate. The product from that reaction (56-1) is then hydrolyzed to the... 

To circumvent any problems caused by cluster quenching by amines on the polymer, a preparation of pyrenylmethyl polyethylenimine was made in which all the primary and almost all the secondary amines were acetylated. Steric factors in the polymer should block quenching interactions with the tertiary amines. In addition, these samples were examined... 

N- Glucuronides have been isolated as urinary or biliary metabolites of many aromatic and aliphatic amines, the reaction being of minor quantitative importance in comparison to N- acetylation and other C- or A/-oxidative processes (see (B-80MI10909)). The only reported example of glucuronidation at a tertiary alicyclic nitrogen appears to be in... 

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