I. F. Leshcheva

Reactions of Hydroxyazolidines with π-Donor Heterocycles. 3. Reaction of 1-Acetyl-5-hydroxypyrazolidines with Oxindoles

The reaction of oxindoles with 5-hydroxypyrazolidines on the surface of potassium fluoride-modified alumina leads to 3-(5-pyrazolidinyl)oxindoles. The structure of these products was studied.

Reactions of hydroxyazolidines with π-donor heterocycles. 2. Reaction of 1-acetyl-5-hydroxypyrazolidines with pyrazol-5-ones on the surface of adsorbents

The reaction of 1-acetyl-2-phenyl-5-hydroxypyrazolidines with pyrazol-5-ones leads to the corresponding 4-(pyrazolidin-5-yl)pyrazolones, which exist mainly in the form of hydroxypyrazoles. The process proceeds on the surface of adsorbents in a nonpolar solvent. The structure and stereochemistry of the bisheterocycles obtained were studied.

Investigation of the three-dimensional structures of a number of N-substituted derivatives of 4-decahydroquinolone by means of 13C NMR spectroscopy

The three-dimensional structures and eonformational compositions of a number of N-substituted 4-decahydroquinolones, particularly the 1-(S)-α-phenylethyl-4-deca-hydroquinolone isomer that is primarily formed in the asymmetric hydride reduction of 1-(S)-α-phenylethyl-Δ9,10-octahydro-4-quinolone and was previously assigned to the trans series on the basis of chiral-optical properties, were investigated by 13C NMR spectroscopy. It is shown by means of NMR data that this compound belongs to the cis series. The lines in the 13C-{1H} NMR spectra of a number of 4-decahydroquinolones were assigned by means of an additive scheme for the 13C chemical shifts, and criteria of the type of fusion of the two rings in the investigated class of heterocyclic compounds were established.

Hydrazones ofα-pyrazolidinylacetoacetic ester

The p-nitrophenylhydrazones and acetylhydrazones of trans-α-(1-acetyl-2-phenyl-3-methyl-5-pyrazolidinyl)-acetoacetic ester have been obtained in the form of a mixture of diastereomeric pairs of syn-isomers. Individual diastereomeric pairs that have been isolated do not undergo any tautomeric conversions in nonpolar solvents. Heterocyclization of these hydrazones is difficult.

Reaction of i-acetyl-2-phenyl-5-hydroxypyrazolidines with alcohols on the surface of adsorbents

A novel method for synthesis of 5-alkoxypyrazolidines on the surface of an adsorbent allows us to obtain derivatives of allyl, tertiary, and chiral alcohols.

Interaction of 5-hydroxypyrazolidines with Ch-acid compounds

The interaction of I-acetyl-2 phenyl-5-hydroxypyrazolidine with carbonyl compounds on the surface of acidic aluminum oxide results in the formation of products in which the hydroxyl group has been replaced by the residue of the carbonyl compound. It has been shown that derivatives of ß-dicarbonyl compounds, under the conditions of the reaction, may undergo subsequent conversions in which one of the carbonyl-containing residues is split off.

Spatial structure of 2-benzoyl-3-methoxy-5-methylisoxazolidine

The nuclear Overhauser effect and x-ray diffraction analysis have been employed to determine the spatial structure of the diastereoisomeric 2-benzoyl-3-methoxy-5-methylisoxazolidines. It has been found that the predominant isomer in the reaction mixture has the cis-configuration.

The 13C NMR spectra, isomerism, and conformational analysis of substituted piperidin-4-ones

The 13C NMR spectra of 15 stereoisomers of 1-mono-, 1,2-di-, and 1,2,5-trisubstituted piperidin-4-ones were investigated, and the stereochemical orientations of the substituents and the conformation relationships were established. For the series of piperidones a method for determination of the absolute confirmation of the C(2) center of the piperidone ring is proposed on the basis of the chemical shifts of the methyl groups in the 1-s-α-phenylethyl substituent at the nitrogen atom in the preferred rotamers with respect to the C(1)-N bond.

Regioselective methylation of 1-benzyl-Δ9, 10-octahydro-4-quinolone

The methylation of 1-benzyl-Δ9,10-octahydro-4-quinolone with methyl iodide in the presence of lithium diethylamide in tetrahydrofuran is a regioselective electrophilic substitution reaction, and, depending on the reaction conditions, takes place in the 3 or 8 position of the quinolone system. Deuteration under the same conditions takes place only in the 3 position.