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Aminomethylation of aurones was studied by using anabasine. The reaction in the case of 6-hydroxyaurones was shown to selectively provide 7-aminomethyl-6-hydroxyaurones, while 5-aminomethyl-6-hydroxy-7-methylaurones could be obtained by transamination of 5-dimethylaminomethyl derivatives of 6-hydroxy-7-methylaurones in the presence of anabasine.

It has been established that on heating, 3-benzoyl-4-hydroxy-1-methyl-4-phenylpiperidine is ring-opened in the presence of arylamines by a type of retroaldol reaction, with subsequent transamination of the intermediate Mannich base and the formation of 3-arylamino-1-oxo-1-phenylpropanes. When using arylhydrazines this γ-piperidol is recyclized with the formation of 1,3-diarylpyrazoles and their 4,5-dihydro derivatives. The mass spectral behavior of a series of 3-arylamino-substituted 1-phenylpropanones has been studied.

The rearrangement of 1-alkyl-2-(carbamoylmethyl)pyrimidinium iodides into substituted 2-alkylaminonicotinamides occurring in alcoholic solutions of amines has been studied. It was shown that in the presence of water the rearrangement of 2-(carbamoylmethyl)-1,4,6-trimethylpyrimidinium iodide is accompanied by the formation of a derivative of 2-oxo-1,2-dihydronicotinic acid, and under the action of ethylamine a “rearrangement and transamination” occurs leading to 2-ethylamino-4,6-dimethylnicotinamide.

A study was carried out on the enamine rearrangement of iodoalkylates of the ethyl ester of 4,6-dimethyl-2-pyrimidinylacetic acid to give ethyl esters of 2-alkylamino-4,6-dimethylnicotinic acid, which proceeds upon the action of various amines. The reaction with amines containing an alkyl substituent different from that at the quaternized nitrogen atom of the pyrimidinium salt leads to the formation of products of rearrangement and transamination. In the presence of water, the rearrangement is accompanied by the formation of the ethyl ester of 1,2-dihydro-2-oxo-4,6-dimethylnicotinic acid.

Reaction of N-acetylindoxyl and 2-methyl-3-ethoxycarbonylpyrrol-2-in-4-one with acetals of N,N-dimethylformamide and N-formylpiperidine has given the enaminoketones. Hydrolysis and transamination of these enaminoketones has been studied. The structures of the products were established by IR, PMR, and 13C NMR spectroscopy.

The reactions of 1,2,3,4-tetrahydro-3-isoquinolone derivatives with dimethylformamide acetal and the hydrolysis and transamination of the resulting enamino amides — 1,2,3,4-tetrahydro-4-dimethylaminomethylene-3-isoquinolone derivatives — were studied. It is shown that 1,2,3,4-tetrahydro-1-phenyl-6,7-dimethoxy-3-isoquinolone can be converted to the corresponding lactim ether. The reactions of the latter with dimethylformamide acetal and hydrazine and the dehydrogenation of this lactim ether in the presence of sodium ethoxide were studied.

A number of quaternary salts of ethyl γ-pyridylbutyrate and diethyl Β-pyridyl-ethylmalonate undergo the Kost-Sagitullin reaction to give N-methyl-2-quinolone and 3-methylaminocarbamoyl-N-methyl-2-quinolone. Rearrangement in the presence of excess aliphatic amines is accompanied by an efficiently proceeding transamination.

The fundamental possibility of carrying out the asymmetric synthesis of 4-piperidones on the basis of the transamination of 1-substituted 2-methyl-4-piperidone methiodides by optically active α-phenylethylamine was demonstrated; the optical yield of the asymmetric transamination is 50%. The occurrence of asymmetric synthesis was confirmed by the isolation of enantiomers of 2-methyl-4-piperidol by reduction of the individual diastereomers of 1-α-phenyl-ethyl-2-methyl-4-piperidone to the corresponding 4-piperidols with subsequent removal of the chiral substituent attached to the nitrogen atom.

Reaction of the methyl iodide of trans-1,2,5-trimethyl-4-piperidone with S-α-phenylethylamine proceeds asymmetrically and leads in 66% optical yield to the formation of the cis- and trans-diastereomeric pair of 1-(α-phenylethyl)-2,5-dimethyl-4-piperidone, in which the new asymmetric centers possess the 2S,5S- and 2S,5R-configurations, respectively. According to x-ray structural analysis, the minor trans-1-(α-phenylethyl)-2,5-dimethyl-4-piperidone component possesses the 2R,5S-configuration. The occurrence of asymmetric synthesis accompanying transamination was confirmed via the preparation of enantiomers of trans-2,5- and trans-1,2,5-trimethyl-4-piperidones.

The lability of the C-N bond in a number of β-amino derivatives of sulfolane was investigated. Alkyl-aryl transamination and a number of reactions of salts of aminosulfolanes with nucleophilic reagents were realized.

In the synthesis of indoles from pyridinium salts the degree of transamination depends on the character of the alkyl group attached to the nitrogen atom of the amine and its nucleophilicity. The yields of indoles decrease as the steric hindrance becomes greater.

The PMR spectrum of the product of reaction of hexamethylcyclotrisilizane with ethylenediamine is investigated, and shows that both linear-ladder and linear polysilazane can arise from the transamination reaction.

The reaction of o-alkylisoureas with azomethines leads to the formation of 4,6-dialkoxy-2-aryl-1-N-amidino-1,2-dihydro-sym-triazines. 4,6-Dialkoxy-2-phenyl-1-N-(4,6-dihydroxy-2-pyrimidinyl)-1,2-dihydro-sym-triazines were obtained by cyclization of these compounds with malonic ester.

We have found that 2-amino-5-phenyl-4-oxazolinone (I) upon treatment with benzylamine and paraform does not undergo the expected aminomethylation reaction, but rather undergoes successive transamination [i], 5ishydroxymethylation, and dehydration reactions, to give 7benzylimino-8-oxo-5-phenyl-l-aza-3,6-dioxabicyclo[3o2.1]octane (II). Compound II was also obtained by an independent synthesis from 2-benzylamino-5-phenyl-4-oxazolinone (III) and formalin

It has been previously shown that quaternary pyridinium salts of the I type are capable of undergoing recyelization under the influence of nueleophilic agents to give aromatic amines [1,2]. It was subsequently established [3] that the rearrangement is complicated by side processes, among which transamination in the step involving open intermediate II plays the primary role. When a bulky substituent such as an isopropyl group is attached to the pyridine nitrogen atom, transamination becomes the principal process and can be used to introduce aromatic groupings into primary and secondary amines.