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Multi-membered N-heterocycles R 0690Aminomethylation by Formaldehyde and Primary Amines of Anionic σ-Adduct Obtained from 2,4-Dinitrophenol and Acetophenone Carbanion. -Mechanistical aspects are discussed. The structure of compound (VIc) is determined by X-ray analysis. -(SHAKHKEL'DYAN, I. V.; LEONOVA, O. V.; ATROSHCHENKO, Y. M.; BOIKOVA, O. I.; BOBRULEVICH, O. Y.; GRINTSELEV-KNYAZEV, G. V.; YAKUNINA, I. E.; SHCHUKIN, A. N.; ALIFANOVA, E. N.; SUBBOTIN, V. A.; Russ.

A series of 6,11-disubstituted 1, 9-dinitro-5-oxa-11-azatricyclo[6.4.0.0 4,9 ]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.Nitroarenes are fairly often involved in the synthesis of polyfunctional N,O-heterocyclic compounds possessing quite a number of useful properties [1]. In continuation of investigations [2-8] on applying anionic σ-adducts of dinitroarenes I to preparation of polyfunctional derivatives of 3-azabicyclo[3.3.1]nonane, an important class of compounds possessing versatile biological activity [9], in the present study syntheses were performed of a series of 6-R-11-R'-1,9-dinitro-5-oxa-11-azatricyclo[6.4.0.0 4,9 ]dodecan-2-ones IIa-IIj. The preparation of compound IIa at reduction of Janovsky σ-adduct of 2,4-dinitrophenol and acetone (Ia) with sodium borohydride was first reported [10], but no reliable proofs of tricyclic compound formation were given. Therefore we carried out a more detailed investigation of the molecular structure of compounds synthesized by means of NMR spectroscopy.The reduction of carbonyl group in oxopropyl and 2-phenyloxoethyl substituents in the Janovsky adducts Ia and Ib was performed with the use of NaBH 4 . This reagent of high chemoselectivity is commonly used for selective reduction of an isolated carbonyl group of a saturated ketone in the presence of a conjugated C=O bond [11]. The forming intermediate secondary alcohols A without separation from the reaction mixture were brought into the Mannich condensation with primary amines and formaldehyde. As a result we obtained in 50-70% yields N,O-containing tricyclic compounds IIaIIj. The maximum yield of the compounds was obtained in a mixture MeCN-water at 20°C and the solution pH 6.0.The structure of 6-R-11-R'-1,9-dinitro-5-oxa-11-azatricyclo[6.4.0.0 4,9 ]dodecan-2-ones IIa-IIj is confirmed by the presence in their IR spectra of strong absorption bands in the region 1545-1550 and 1340-1365 cm -1 corresponding to the stretching vibrations of nitro groups. The vibrations of the C=O bond of the endocyclic keto group give rise to absorption in the region 1725-1755 cm -1 . The absorption band at lower frequencies (1085-1145 cm -1 ) belongs to the stretching vibrations of the ether group COC in pyran ring.The assignment of the signals in the NMR spectra of compounds synthesized was done with the help of twodimensional homo-(COSY, NOESY) and heteronuclear (HSQC, HMBC) spectroscopy ensuring the reliable proof of the structure and conformation of the compounds. For instance, in the 1 H NMR spectrum of compound IIa appear 11 signals of chemically or magnetically nonequivalent protons, and in the 13 C NMR spectrum signals...

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2001 multi-membered N-heterocycles multi-membered N-heterocycles R 0690 41 -189 3-Azabicyclo[3.3.1]nonane Derivatives. Part 3. Synthesis of 3-Substituted 9-Acetonyl-1,5-dinitro-3-azabicyclo[3.3.1]non-6-en-8ones by Mannich Condensation of the Janovsky σ-Adduct of 2,4-Dinitrophenol with Acetonide Ion. --(LEONOVA, O. V.; SHAKHKEL'DYAN, I. V.; GRUDTSYN, YU. D.; ATROSHCHENKO, YU. M.; ALIFANOVA, E. N.; GITIS, S. S.; CHUDAKOV, P. V.; NIKIFOROVA, E. G.; ALEKHINA, N. N.; KAMINSKII, A. YA.; Russ.