Yu. T. Struchkov

New pathway for the disproportionation of hydrothiochromenes and structural studies of the resulting compounds

A new pathway for the disproportionation of hydrothiochromenes under the influence of protic acids, which consists in intermolecular hydride transfer of a hydrogen from the alicycle and leads to the development of a hydrothiochroman, was developed. Correlation results that confirm the structures and conformational peculiarities of the resulting compounds were obtained by PMR spectroscopy and x-ray diffraction analysis.

Saturated nitrogen-containing heterocycles. 16. Catalytic synthesis of N-arylperhydroacridines

Catalytic hydroamination of methylene-2,2′-dicyclohexanone in the presence of substituted anilines or nitrobenzenes involves the formation of N-arylperhydroacridines. The stereoisomeric composition and yields of the latter are determined by the nature and position of the substituent in the aromatic ring of the aminating agent. The structure of isomeric N-arylperhydroacridines was established from data of 13C NMR spectroscopy and x-ray diffraction analysis.

Reactions of sym-octahydrothioxanthylium salts with bases and structure of 4-(sym-octahydrothioxanthen-9-yl)-1,2,3,5,6,7,8-heptahydro-2H-thioxanthene

The reaction of sym-octahydrothioxanthylium salts with pyridine or aqueous sodium bicarbonate leads to the formation of 4-(sym-octahydrothioxanthen-9-yl)-1,2,3,5,6,7,8-heptahydro-2H-thioxanthene, whose structure was established by x-ray diffraction analysis.

Saturated nitrogen-containing heterocycles. 13. Perhydroacridines. Synthesis and stereochemistry

The configurations of the perhydroacridines formed in the catalytic hydroamination of threo-methylenedicyclohexanone and the product of its cyclization — 2-hydroxy-2,3-tetramethylenebicyclo[3.3.1]nonan-9-one — were established by means of the 13C NMR spectra and alternative synthesis. It is shown that isomers with cis-anti-cis and cis-syn-cis configurations are formed as a result of the reactions. The results of x-ray diffraction analysis are presented for cis-syn-cis-N-(2-hydroxyethy1)perhydroacridine.

Crystal and molecular structure of 7,7-dimethyl-2,3-di(4-methoxyphenyl)-5-oxo-5,6,7,8-tetrahydroquinoline

An x-ray crystallographic investigation of 7,7-dimethyl-2,3-di(4-methoxyphenyl)-5-oxo-5,6,7,8-tetrahydroquinoline, obtained by the hydrolysis of its oxime, was undertaken. The oxime, together with the isomeric oxime of 7,7-dimethyl-2,4-di(4-methoxyphenyl)-5-oxo-5,6,7,8-tetrahydroquinoline, is formed in the reaction of 5,5-dimethyl-2-[1,3-di(4-methoxyphenyl)-3-oxopropyl]cyclohexane-1,3-dione with hydroxylamine hydrochloride.

Conversion of trans, trans-1-methoxy-3,5-diaryl-2-oxabicyclo[4.4.0]dec-3-enes into hemidithioacetals and 4H-thiopyrans. Structure of trans, trans-1-mercapto-3-phenyl-5-(4-methoxyphenyl)-2-thiabicyclo[4.4.0] dec-3-ene

The conversion of trans,trans-1-methoxy-3,5-diaryl-2-oxabicyclo[4.4.0]dec-3-enes into trans,trans-1-mercapto-3,5-diaryl-thiabicyclo[4.4,0]dec-3-enes or 2,4-diaryl-5,6-tetramethylene-4H-thiopyrans, which takes place when hydrogen Sulfide is reacted with the acetals in acetic acid with the use of gaseous hydrogen chloride as a catalyst, has been described. A mechanism for the reaction has been proposed. The structure and confirmations of the molecules have been determined by x-ray diffraction analysis and 13C NMR.

Saturated nitrogen-containing heterocycles. 12. Structural studies of cyclopenta(b)pyrrolidinylalkanols

Abstract13C NMR spectroscopy and x-ray diffraction structural analysis were used to establish the stereochemistry of 3-[N-methyl-2-cyclopenta(b)pyrrolinyl]-1-propanol and its acetyl derivative. The absolute configuration was determined for 3-[N-methyl-2-cyclopenta(b)pyrrolidinyl]-1-propanol acid tartrate dihydrate and the conformational aspects of its cation and tartrate anion were studied.

Saturated nitrogen-containing heterocycles. 11. The synthesis and structural studies of octahydroindolylalkanols

A catalytic synthesis was carried out for 3-(1-R-2-octahydroindolyl)alkanols using nickel promoted by ruthenium, Raney nickel, and Raney cobalt previously treated with acetic acid. An x-ray diffraction structural study of the acid tartrate of 3-(1-methyl-2-octahydroindolyl)-1-propanol gave the absolute configuration and conformational and structural features of the cation and tartrate anion.

Crystal and molecular structure of 2-benzoly-5-phenylpyrrole

An x-ray diffraction investigation of 2-benzoyl-5-phenylpyrrole, whose molecules are combined as dimers in the crystal, has been carried out. The bond lengths and angles have been presented.

Formation of 3,5-diphenyl-2-thiabicyclo[4.4.0]dec-Δ1,6-ene under the conditions of the pummerer reaction and its structure

The Pummerer rearrangement was investigated in the case of 3,5-diphenyl-2-thiabicyclo [4.4.0]decane S-oxide. It is shown that, of the two possible isomers, this compound forms only 3,5-diphenyl-2-thiabicyclo[4.4.0]dec-Δ1,6-ene under the conditions of the Pummerer reaction; a secondary transformation, viz., disproportionation of the latter to 3,5-diphenyl-2-thiabicyclo[4.4.0]decane and 2,4-diphenyl-5, 6-tetramethylenethiopyrylium acetate, is observed. 3,5-Diphenyl-2-thiabicyclo[4.-4.0] dec-Δ1,6-ene was subjected to an x-ray diffraction study; it was proved unambiguously that the C1=C6 double bond has a length of 1.335 Å and that the dihydrothiopyran and cyclohexene rings have a distorted half-chair conformation: the dihedral angles between the phenyl rings and the planar fragment of the heteroring are 76.8 and 93.2 °C.