Synthesis of 4-nitro-3,3,7-trimethyl-2-(2-hydroxystyryl)indolenines

The previously unknown hydroxystyrylindolenines have been synthesized by the direct condensation of 4-nitro-2,3,3,7-tetramethylindolenine with substituted salicylaldehydes. The structure of the prepared compounds has been confirmed by spectroscopic investigation.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 340–342, March, 1990.     

An efficient synthetic route to chiral 4-alkyl-1,2,3,4-tetrahydroquinolines: enantioselective synthesis of (R)-4-ethyl-1,2,3,4-tetrahydroquinoline

An efficient synthetic route to non-racemic chiral 4-alkyl-1,2,3,4-tetrahydroquinoline is described. (4R)-4-Ethyl-1,2,3,4-tetrahydroquinoline was obtained by the organoaluminum promoted modified Beckmann rearrangement involving the oxime sulfonate of (3R)-3-ethylindan-1-one. The required optically active indanone was obtained via an asymmetric conjugate reduction of (E)-ethyl 3-phenylpent-2-enoate.     

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.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1085–1088, August, 1987.     

Crystal structure of 4,5-bis(4-dimethylaminophenyl)-2-(4-nitrophenyl)imidazole.

A nonlinear optical chromophore, 4,5-bis(4-dimethylaminophenyl)-2-(4-nitrophenyl)imidazole, was investigated by X-ray crystallography. The study focused on coplanarity among several aromatic rings, including phenyls and imidazole. Two phenyl rings with NMe2 groups are twisted by 46.39(3) degrees from each other. However, they are twisted by 23.05(5) degrees and 46.84(3) degrees from the imidazole, respectively. These unequal twists were elucidated by different conjugation pathways from the donors to the acceptor. The phenyl ring with the NO2 group is twisted by only 6.76(6) degrees from the imidazole.     

Crystal structure of 3,3-dichloro-N-p-methoxyphenyl-4-(2-phenylstryl)-2-azetidinone.

3,3-Dichloro-N-p-methoxyphenyl-4-(2-phenylstryl)-2-azetidinone (C22H15Cl2NO2) was studied by X-Ray analysis, which indicated a monoclinic space group, P2(1)/c, with a = 9.619(5), b = 13.879(4), c = 14.161(5)A, beta = 100.16(3)degrees, V = 1860.8(13)A3, Z = 4, Dc = 1.414 g cm(-3), micro(Mo Kalpha) = 0.366 mm(-1) and F000 = 816. The structure was solved by direct methods and refined to R = 0.041 for 4026 reflections [I > 2sigma(I). The beta-lactam ring (2-azetidinone) has antimicrobial affects. The substituents of the methoxyphenyl and phenyl substituents do not change the activity property of the beta-lactam ring, and the activity properties depend on the planarity of the beta-lactam ring.     

An efficient synthesis of optically pure (S)-2-functionalized 1,2,3,4-tetrahydroquinoline

Using a copper-catalyzed coupling reaction of amino acid and aryl halide, followed by intramolecular cyclization of N-aryl-1-hydroxyl-3-propylamines under the Swern’s condition as the key steps, (S)-2-hydroxymethyl-1,2,3,4-tetrahydroquinoline was synthesized as an example of optically pure 2-functionalized 1,2,3,4-tetrahydroquinolines.     

Crystal structure of bis(2-(2-thiazolylazo)-4-methylphenol)cobalt(III)chloride.

The reaction between CoCl2 x 6H2O and 2-1-(2-thiazolylazo)-p-cresol (TAC) in acetone resulted in six coordinated cobalt(III) complex, [Co(TAC)2]Cl3. Two TAC ligands coordinate with cobalt ion forming four five membered chelate rings. The cobalt ion is octahedrally coordinated by a phenolic oxygen, azo nitrogen and nitrogen in thiazole rings. Three chloride ions are disordered.     

Crystal structure of 4-(4'-diethylaminophenyl)-6-(4-methoxyphenyl)-(2-pyrrolidin-1-yl)-pyridine-3-carbonitrile.

4-(4'-Diethylaminophenyl)-6-(4-methoxyphenyl)-(2-pyrrolidin-1-yl)-pyridine-3-carbonitrile (DMPPC) was studied by X-ray diffraction methods due to its non-linear optical properties. The pyrrolidine and pyridine rings adopt half-chair and planar conformations, respectively. The molecules in the crystal are stabilized by C-H...O and C-H...N types of intermolecular interactions in addition to van der Waals forces.     

Molecular structure and conformational analysis of chirai (−)-3-(4-bromobenzylidene)-1-isopropyl-2-methoxy-4-methylcyclohexene

(–)-3-(4-Bromobenzylidene)-1-isopropyl-2-methoxy-4-methylcyclohexene, capable of inducing spiral supramolecular ordering when introduced to nematic and some smectic mesophases, has been studied by an X-ray structural analysis. The crystals are orthorhombic; at 20 °Ca = 6.055(1),b = 13.282(3),c=20.734(4) Å,V=1668(1) ų,d _calc = 1.380 g cm^–3, space groupP2 ₁2₁2₁ Z=4. The cyclohexene ring has a conformation intermediate between a sofa and a half-chair. The methyl and methoxyl groups are in asyn orientation with respect to the mean plane of the cycle. The angle between the plane of the aryl substituent and the exocyclic double bond is 33°. The observed distortions of bond angles at unsaturated carbon atoms are typical of derivatives of benzylidenecyclohexene. Molecular mechanics calculations demonstrated that the conformation observed in the crystalline state is not the most favorable, and this conformation is stabilized through intermolecular interactions upon stacking in crystals. It was shown that the relative orientation of the methyl and methoxyl groups as well as the orientation of the aryl substituent substantially affect the conformation of the cyclohexene ring.Deceased.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2437–2442, December, 1995.     

Crystal and molecular structure of an active carbinolamide: 4-hydro-4-dimethoxymethyl-6-isopropyl-2-oxo-2,3-dihydro(6H)-1,3-oxazine

The crystal and molecular structure of the title compound has been determined by single-crystal x-ray diffraction techniques. The compound is of interest because of its own intrinsic anti-tumor activity and because it is also a common moiety of a series of more active anti-tumor agents, the maytansinoids. The compound crystallizes in the space group Pī with 2 molecules in a unit-cell of dimensions a = 6.912 Å,b = 7.219 Å,c = 15.272 Å, α = 119.96°, β = 104.30° and γ = 96.04°. The structure was solved by direct methods and refined to a final value of R = 0.063.