Yu. M. Atroshchenko

Synthesis and Structure of 1,9-Dinitro-5-oxa-11-azatricyclo[6.4.0.04,9]dodecan-2-one

A series of 6,11-disubstituted 1,9-dinitro-5-oxa-11-azatricyclo[6.4.0.04,9 ]dodecan-2-ones were prepared from anionic adducts of 2,4-dinitrophenol with propanone and 2-phenylethanone carbanions by successive selective reduction with sodium borohydride and aminomethylation with formaldehyde and primary amines. By spectral methods and by quantum-chemical calculations following PM3 method the structure of the molecules synthesized was shown to contain all the three rings in a chair form with equatorial substituents in positions 6 and 11.

3-azabicyclo[3.3.1]nonane derivatives: IX. Synthesis and molecular structure of 3-azabicyclo[3.3.1]nonane-1,5-diamines in solution and in solid state

During catalytic reduction with hydrogen on nickel of a series of 3-substituted 1,5-dinitro-3-azabicyclo-[3.3.1]non-6-enes alongside nitro groups reduction occurred also hydrogenation of the double bond. New diamines of the 3-azabicyclo[3.3.1]nonane series were synthesized, and their structure was established by means of IR, 1H and 13C NMR spectroscopy and X-ray diffraction study.

Regioselectivity in the reactions of the acetonate ion with electron-deficient arenes

The reactions of the acetonate ion with 1,3-dinitro-5-X-, 1,3-X2-5-nitro- (X = NO2, CN, COOCH3, CONH2, COO–, and H), and 1,3,5-tricyanobenzenes were studied by 1H NMR and electronic absorption spectroscopy and by quantum-chemical methods. The kinetic factor is decisive for the initial attack of the carbanion on the C(2) atom of unsymmetrical arenes. However, σ-adducts in which a nucleophile is added to the C(4) atom are more stable thermodynamically. In the case of 1,3-X2-5-nitrobenzenes (X = CN, COOCH3, or CONH2), the σ-adducts with the acetonate group in para-position to the X group unexpectedly proved to be very stable. The structures of the σ-adducts based on trinitro- and 1,3-dinitro-5-cyanobenzenes were determined by X-ray diffraction analysis. Quantum-chemical calculations (the AM1 and PM3 semiempirical methods and the density functional method) were used to interpret the reaction regioselectivity and the molecular and electronic structures of the σ-adducts.

Synthesis of new aminocyclitols by selective epoxidation of N-benzyl-N-methyl-2-cyclohepten-1-amine and tert-butyl 4-[benzyl(methyl)amino]-2,3,4,7-tetrahydro-1H-azepine-1-carboxylate

Synthesis of N-benzyl-N-methyl-2-cyclohepten-1-amine and tert-butyl 4-[benzyl(methyl)amino]-2,3,4,7-tetrahydro-1H-azepine-1-carboxylate from cyclic allyl acetates was performed. The features of stereoselective epoxidation of these substrates were investigated. The subsequent epoxide opening with water led to the formation of new pseudosaccharides, (1RS,2RS,3RS)-3-[benzyl(methyl)amino]-1,2-cycloheptanediol, (1RS,2RS,3SR)-3-[benzyl(methyl)amino]-1,2-cycloheptanediol, and (3RS,4RS,5RS)-3-[benzyl(methyl)amino]-4,5-azepanediol.

Amino- and hydroxymethylation of hydride adducts of 2-hydroxy-3,5-dinitropyridine

A series of 1,5-dinitro-3,3-diazabicyclo[3.3.1]nonan-2-one derivatives has been synthesized by Mannich condensation of the hydride adduct of 2-hydroxy-3,5-dinitropyridine with formaldehyde and primary amines. The structure of the obtained compounds was proved by NMR spectroscopy.

Synthesis of 2,6-diazatricyclododecanes from 2-hydroxy-3,5-dinitropyridine

We found that treatment of 2-hydroxy-3,5-dinitropyridine (I) in acetone first with secondary or tertiary amine, e.g., 3,5-dimethylpiperidine, and then with an aminomethylating mixture in the presence of an acid leads to the formation of 6-substituted 4,8-dinitro-2,6diazatricyclo[6.4.0.0]dodecane-3,11-diones IIIa and IIIb. The product structure was determined on the basis of their IR and H and C NMR spectra and the results of two-dimensional homo(COSY) and heteronuclear (HMBC, HSQC) correlation experiments.

Selective reduction of 6-substituted 1,5-dinitro-3-azabicyclo[3.3.1]non-6-enes

Reduction of 6-substituted 1,5-dinitro-3-azabicyclo[3.3.1]non-6-enes gives either saturated 1,5-diamino-3-azabicyclo[3.3.1]nonane or unsaturated 1,5-diamino-3-azabicyclo[3.3.1]non-6-enes, depending on the conditions and nature of substituent in the substrate.

Aminomethylation by Formaldehyde and Primary Amines of Anionic σσ-Adduct Obtained from 2,4-Dinitrophenol and Acetophenone Carbanion

By condensation of 2,4-bis(aci-nitro)-3-(2-phenyl-2-oxoethyl)cyclohex-5-en-1-one with formaldehyde and primary amines a series of N-substituted 9-(2-phenyl-2-oxoethyl)-1,5-dinitro-3-azabicyclo[3.3.1]non-7-en-6-ones was synthesized. With the use of X-ray analysis the cyclohexenone fragment in the 3-(2-bromoethyl)-1,5-dinitro-9-(2-phenyl-2-oxoethyl)-3-azabicyclo[3.3.1]non-7-en-6-ones was established to exist in sofa conformation, and the nitrogen-containing ring to have the chair conformation with equatorial orientation of substituents in 3 and 9 positions. The regio- and stereoselectivity of the reaction under study was interpreted relying on the quantum-chemical calculations by AM1 and PM3 procedures.

VI. Synthesis of heterocyclic analogs of γ-aminobutyric acid from 3,5-dinitrobenzoic acid

A series of 7-carboxy-3-R-1,5-dinitro-3-azabicyclo[3.3.1]non-6-enes was synthesized by reduction of 3,5-dinitrobenzoic acid with sodium borohydride followed by Mannich reaction with formaldehyde and primary amines. The mechanism of decomposition under electron impact of the 3-azabicyclo[3.3.1]nonane was established. Enthalpies of formation of compounds synthesized were calculated by semiempirical PM3 method.

Structure features of ions and ion pairs of nitroarene anionic σ-complexes in aprotic solvents

Abstract The structure of ions and ion pairs of Meisenheimer and Janovsky σ-complexes of 1,3,5-trinitrobenzene has been studied by derivative spectroscopy and semiempirical quantum chemical PM3 and CNDO/S methods. On the base of comparison of theoretical and experimental electronic absorption spectra the three types of co-ordination of anion and cation have been defined. It was established that the structure of ion pairs is determined by the nature of the substituents of the pyramidal unit.