N. M. Kolyadina

Synthesis and molecular structure of 2,3,4,5-tetrahydro-1H-3-benzazepine derivatives and dimethyl 4-cyano-2,3,6,7-tetrahydro-1H-3-benzazonine-5,6-dicarboxylate

A study was carried out on the direction of 1,2,3,4-tetrahydroisoquinolinium quaternary salt rearrangements by the action of base with or without dimethyl acetylenedicarboxylate. These quaternary salts containing a methylene group at the nitrogen atom, are converted in the presence of base through intermediate N-ylides into the Stevens rearrangement products, namely, tetrahydro-3-benzazepines. Upon the addition of dimethyl acetylenedicarboxylate as an electrophilic trap, this diester adds at the carbanion site of the ylide with subsequent recyclization of the piperidine fragment to give a 2-benzazonine derivative with an unusual 4,5-positioning of the olefin bond in the nine-membered heterocycle. An X-ray structural analysis established the molecular structures of 2-cyano-3-methyl-2,3,4,5-tetrahydro-1H-3-benzazepine and dimethyl 4-cyano-2,3,6,7-tetrahydro-1H-3-benzazo-nine-5,6-dicarboxylate.

Dimethyl 2-[22,24-dimethyl-23-oxo-8,11,14-trioxa-25-aza­tetra­cyclo­[19.3.1.02,7.015,20]penta­cosa-2,4,6,15(20),16,18-hexaen-25-yl]but-2-enedioate

The title compound, C29H33NO8, is a product of the Michael addition of the cyclic secondary amine subunit of the aza-14-crown-4 ether to dimethyl acetylenedicarboxylate. The piperidinone ring exhibits a distorted chair conformation, and the dimethyl ethylenedicarboxylate fragment has a cis configuration with a dihedral angle of 78.96 (5)° between the two carboxylate groups. The crystal packing is stabilized by weak C—H⋯O hydrogen bonds.

Dimethyl 2-[24-acetyl-28-oxo-8,11,14-trioxa-24,27-diaza­penta­cyclo­[19.5.1.122,26.02,7.015,20]octa­cosa-2,4,6,15(20),16,18-hexaen-27-yl]but-2-enedioate

The title compound, C31H34N2O9, is a product of the Michael addition of the cyclic secondary amine subunit of the (bispidino)aza-14-crown-4 ether to dimethyl acetylenedicarboxylate. The molecule comprises a tricyclic system containing the aza-14-crown-3 ether macrocycle and two six-membered piperidinone rings. The aza-14-crown-3-ether ring adopts a bowl conformation with a dihedral angle between the planes of the fused benzene rings of 51.14 (5)°. The central piperidone ring has a boat conformation, whereas the terminal piperidone ring adopts a chair conformation. The dimethyl ethylenedicarboxylate fragment has a cis configuration with a dihedral angle of 56.56 (7)° between the two carboxylate groups. The crystal packing is stabilized by weak C—H⋯O hydrogen bonds.

24-Acetyl-8,11,14-trioxa-24,27-diaza­penta­cyclo­[19.5.1.122,26.02,7.015,20]octa­cosa-2,4,6,15(20),16,18-hexaen-28-one

The title compound, C25H28N2O5, is a product of the Petrenko–Kritchenko condensation of N-acetylpiperidone with 1,5-bis(2-formylphenoxy)-3-oxapentane and ammonium acetate. The molecule comprises a fused pentacyclic system containing an aza-14-crown-3-ether macrocycle, two piperidone and two benzene rings. The aza-14-crown-3-ether ring adopts a bowl conformation. The dihedral angle between the benzene rings fused to the aza-14-crown-4-ether unit is 70.18 (4)°. The central piperidone ring has a boat conformation, whereas the terminal piperidone ring adopts a chair conformation. The conformation of the central piperidone ring is determined by two intramolecular N—H⋯O hydrogen bonds. In the crystal, molecules are linked by weak C—H⋯O interactions into chains along [010].

Indolopyridines with a bridging heteroatom. 9. Synthesis, structure, and thermolysis of 5-hydroxy-5-(2-pyridyl)-fluorene and 4-azafluorene

Treatment of fluorenone or 4-azafluoren-9-one with 2-pyridyllithium gives 45-hydroxy-5-(2-pyridyl)fluorene and its aza analog. The structure of the former has been studied by x-ray crystallography. It was found that, in contrast to the non-condensed diaryl-2-pyridylcarbinols, these alcohols do not undergo acid catalyzed dehydration and heterocyclization. Under pyrolytic conditions. 5-pyridylfluorenol undergoes fission to form fluorenone.

Oxidation reactions of azines: XIII. Synthesis, molecular structure, and oxidation reactions of 3-methyl-3,3′,4,4′,5,6-hexahydro-1′H,2H-spiro[benzo[f]isoquinoline-1,2′-naphthalen]-1′-one

The condensation of 3,4-dihydronaphthalen-1(2H)-one with methylamine and formaldehyde in acid medium gave N,N-bis(1-oxo-1,2,3,4-tetrahydronaphthalen-2-ylmethyl)methanamine hydrochloride which was converted into 3-methyl-3,3′,4,4′,5,6-hexahydro-1′H,2H-spiro[benzo[f]isoquinoline-1,2′-naphthalen]-1′-one by heating in 48% aqueous HBr or 50% H2SO4. Oxidation of the spiro compound with KMnO4 initially involved the methylene group of the allylamine fragment with formation of the corresponding lactam which then underwent cis-dihydroxylation at C4a and C10b. Oxidation of the same compound with KMnO4 in the presence of some CH acids (trifluoroacetone and 4-bromoacetophenone) or aromatic amines (4-fluoroaniline and 2-bromo-4-nitroaniline) afforded, respectively, 4-acylmethylidene or 4-arylimino derivatives via C-C or C-N cross-coupling at the 4-position.

Template Effect of Pyridinium Salts in the Synthesis of Crown-meso-Tetraphenylporphyrin

Using pyridine in the presence of pyridinium salts as a reaction medium was suggested for the synthesis of crown-mesotetraphenylporphyrin from pyrrole and podand dialdehyde. We expected that the absence of a free acid in the reaction mixture would minimize the linear polymerization rate of the reactants. Use of the proposed reaction medium has almost doubled the yield as compared to the original published synthetic procedure for the target porphyrin and facilitated purification due to a smaller amount of polymeric impurities. Quantum chemical simulations have demonstrated that the podand precursor could form H-bonded complexes with protonated pyridine and thus become pre-organized for the formation of a porphyrinic macrocycle. The same reaction with benzaldehyde did not produce even trace amounts of the porphyrin. Obviously, this is caused by the higher complexation energy for the podand-pyridinium system compared to benzaldehyde-pyridinium (calculated values are 36 and 24 kcal/mol, respectively).

Synthesis of quaternary salts, anhydrobases, and 9-(1,2-dimethoxycarbonyl-3-benzoyl-7-indolizinylmethylene)-4-azafluorene based on 9-(γ-pyridylmethylene)azafluorenes

The ratios ofE- toZ-isomers of the quaternary salts prepared by mono- and diquaternization of 9-(γ-pyridylmethylene)-1-(4)-azafluorenes with iodomethane or bromoacetophenone have been determined. Conversion of the diphenacyl 9-(γ-pyridyl)-4-azafluorenium bromide into the corresponding anhydrobase (diylide), and also its condensation with acetylenedicarboxylate diesters to give 9-(1,2-dimethoxycarbonyl-3-benzoyl-7-indolizinylmethylene)-4-azafluorene have been carried out.

9-(β-pyridylmethylene)-4-azafluorene synthesis of the Z- and E-isomers of its methiodides and reduction of the Z-isomer

The 9-(β-pyridylmethylene)-4-azafluorene was obtained as the mixture of the Z- and E-isomers. Condensation of 4-azafluorene with methiodides of 3-formylpyridine afforded the methiodides of these isomers which were isolated in discrete form. Their configuration was established. It was established using the example of the reduction of the methiodide of the Z-isomer by sodium borohydride that the β-pyridinium portion of this quaternary salt is completely reduced to the piperidyl.