Reaction of 6,11-dihydrodibenzo[b,e]thiepin-11-carbonitrile with 1,2-dibromoethane, a reinvestigation. Formation of 11,12-dihydro-6H-6,12-methanodibenzo[b,f]thiocin-12-carbonitrile

1987 ◽  
Vol 52 (9) ◽  
pp. 2281-2294 ◽  
Author(s):  
Karel Šindelář ◽  
Miloš Buděšínský ◽  
Tomáš Vaněk ◽  
Jiří Holubek ◽  
Emil Svátek ◽  
...  
Keyword(s):  
Tetrabutylammonium Bromide ◽  
Crystallographic Analysis ◽  
Preparative Hplc ◽  
Similar Reaction ◽  
X Ray ◽  
Cyanide Anion ◽  
Lithium Aluminium ◽  
The One ◽  
Benzyltriethylammonium Chloride ◽  
C Nmr

Reinvestigation of the minor product of reaction of 6,11-dihydrodibenzo[b,e]thiepin-11-carbonitrile (I) with 1,2-dibromoethane in the presence of tetrabutylammonium bromide or benzyltriethylammonium chloride and 50% sodium hydroxide by means of 1H and 13C NMR spectroscopy led to the formula XI named in the title, which was confirmed by X-ray crystallographic analysis. The product of a similar reaction, carried out in dimethyl sulfoxide in the presence of potassium carbonate at 100 °C was identified as the stereoisomeric mixture of 11,11'-ethylenebis(6,11-dihydrodibenzo[b,e]thiepin-11-carbonitriles) (XII) which was separated to the components by preparative HPLC. The title compound XI was oxidized to the sulfoxide XIII and the sulfone XIV, and was transformed by reduction and the following methylation to amines XV and XVI. The reduction of the vinyl nitrile III with lithium aluminium hydride is complicated on the one hand by allylic rearrangement, and with cyanide anion abstraction on the other, the products being (E,Z)-mixture of 3-(6,11-dihydrodibenzo[b,e]thiepin-11-ylidene)propylamines (XVII) and 11-vinyl-6,11-dihydrodibenzo[b,e]thiepin (X). The amine XVI is devoid of thymoleptic activity.

Selenium coronands. A novel conformational pair

1988 ◽  
Vol 66 (11) ◽  
pp. 2956-2958 ◽  
Author(s):  
B. Mario Pinto ◽  
Blair D. Johnston ◽  
Raymond J. Batchelor ◽  
Frederick W. B. Einstein ◽  
Ian D. Gay
Keyword(s):  
Nmr Spectra ◽  
Crystallographic Analysis ◽  
The Novel ◽  
Torsion Angles ◽  
X Ray ◽  
Structure Formula ◽  
Independent Molecules ◽  
Similar Conformation ◽  
C Nmr

The synthesis and characterization of the novel selenium coronands, 1,3,7,9-tetraselenacyclododecane 1a, 1,3,7,9,13,15-hexaselenacyclooctadecane 2a, the corresponding β-gem-dimethyl derivatives 1b, 2b, and 1,5,9,13-tetraselenacyclohexadecane 3, and 1,5,9,13,17,21-hexaselenacyclotetracosane 4 are described. X-ray crystallographic analysis of 1a reveals three independent molecules that exist in two distinct conformations, one molecule having approximate two-fold symmetry together with two molecules (of similar conformation) each having crystallographic [Formula: see text] symmetry. The conformations are denoted as [3333] or [66]. Whereas one resembles that of cyclododecane and tetrathia-12-crown-4 with respect to torsion angles, the other resembles that of tetraoxa-12-crown-4. The solid state CP-MAS 77Se and 13C nmr spectra are interpreted in light of the crystallographic information. Crystal structure: formula Se4C8H16; fw = 428.05; monoclinic, P21/c; Z = 8; a = 15.823(2) Å, b = 5.534(1) Å, c = 27.962(5) Å, β = 92.26(1)°; V = 2446.6 Å3; T = 200 K; R = 0.027 for 2162 observed data (I ≥ 2.5σ(I)).

(3E)-5-Hydroxy-3-[5-(hydroxymethyl)furan-2-ylmethylene]-1-benzofuran-2(3H)-one

2007 ◽  
Vol 63 (11) ◽  
pp. o4354-o4354
Author(s):  
Hong-Yan Ma ◽  
Ji Shi ◽  
Chang-Hong Wang ◽  
Zheng-Tao Wang
Keyword(s):  
Hydrogen Bonds ◽  
Spectroscopic Data ◽  
Furan Ring ◽  
Crystallographic Analysis ◽  
Relative Configuration ◽  
X Ray ◽  
H Nmr ◽  
Compound C ◽  
A Chain ◽  
C Nmr

The title compound, C14H10O5, was isolated from Senecio cannabifolius Less var. integrifolius aqueous extract. The structure was elucidated on the basis of spectroscopic data, including MS, 1H NMR and 13C NMR, and the relative configuration was confirmed by X-ray crystallographic analysis. The benzofuran ring is almost coplanar with the furan ring [dihedral angle = 10.47 (15)°]. A chain is formed through supramolecular R 2 2(10) synthons and three-centre hydrogen bonds.

Far-red absorbing azodipyrrin dyes — Synthesis, X-ray crystallographic, and spectral characterization of 1,9-diazodipyrrins and their metal complexes

2011 ◽  
Vol 89 (4) ◽  
pp. 481-487 ◽  
Author(s):  
Yan Li ◽  
David Dolphin
Keyword(s):  
Metal Complexes ◽  
Zinc Complex ◽  
Nickel Complexes ◽  
Crystallographic Analysis ◽  
Zinc Complexes ◽  
Spectral Characterization ◽  
X Ray ◽  
Almost All ◽  
C Nmr

A series of novel 1,9-diazodipyrrins (4) were readily synthesized by reacting aryldiazonium salts with 5-aryldipyrromethanes under both acidic and basic conditions. The zinc complex of 1,9-diphenylazodipyrrin (5aZn) was confirmed by X-ray crystallographic analysis, and 1,9-diazodipyrrins and their zinc and nickel complexes (5M) were characterized by 1H and 13C NMR, IR, UV–vis, and MS. All of the metal complexes absorb almost all colours of the rainbow; the absorption maximums are >650 nm and the half-band widths are over 100 nm. The fluorescence of the zinc complexes of 1,9-diphenylazodipyrrin (5aZn) and 1,9-di(2-iodophenylazo)dipyrrin (5cZn) were also explored.

Synthesis and characterization of novel azo-embedded N-confused tetraphenylporphyrin

2009 ◽  
Vol 13 (02) ◽  
pp. 215-222 ◽  
Author(s):  
Motoki Toganoh ◽  
Takayoshi Hihara ◽  
Kentaro Yonekura ◽  
Yuichi Ishikawa ◽  
Hiroyuki Furuta
Keyword(s):  
Absorption Spectrum ◽  
Effective Interaction ◽  
Coupling Reaction ◽  
Crystallographic Analysis ◽  
Synthesis And Characterization ◽  
X Ray ◽  
H Nmr ◽  
Cis Isomer ◽  
C Nmr

A unique class of azo porphyrin, 5,10,15,20-tetraphenyl-21-phenylazo-(2-aza-21-carbaporphyrin 1, in which an azophenyl group is embedded in N -confused porphyrin, was synthesized and characterized by 1 H NMR, 13 C NMR, UV-vis absorption, MS, and X-ray crystallographic analysis. Synthesis of 1 was achieved through a coupling reaction of 21-amino N -confused tetraphenylporphyrin with nitrosobenzene and subsequent deoxygenation of resulting azoxy derivative with a trioxo rhenium(VII) N -fused porphyrinato catalyst. The azo-conjugate molecule was exclusively obtained as a trans-isomer and no isomerization to the cis-isomer was observed under thermal or photoirradiation. The absorption spectrum of 1 shows a moderate red-shift due to the effective interaction between the porphyrinic π-system and the connecting azophenyl group. Upon protonation, this effect is essentially lost as a result of removing degeneracy of LUMO and LUMO+1.

Synthesis and X-ray powder diffraction data of cis-4-(4-methoxyphenyl)-3-methyl-6-nitro-2-phenyl-1,2,3,4-tetrahydroquinoline

2013 ◽  
Vol 28 (4) ◽  
pp. 307-311 ◽  
Author(s):  
M.A. Macías ◽  
J.A. Henao ◽  
Arnold R. Romero Bohórquez ◽  
Vladimir V. Kouznetsov
Keyword(s):  
Powder Diffraction ◽  
Alder Reaction ◽  
Diels Alder ◽  
Gas Chromatography Mass Spectrometry ◽  
One Pot ◽  
X Ray ◽  
Cell Parameters ◽  
Diels Alder Reaction ◽  
The One ◽  
C Nmr

The 2,4-diaryl 1,2,3,4-tetrahydroquinoline derivative (1), described in the title (Chemical formula: C23H22N2O3), was synthesized via the “one-pot” three-component imino Diels–Alder reaction catalyzed by Cu(OTf)2. Molecular characterization was performed by 1H and 13C NMR, Fourier transform-infrared, and gas chromatography-mass spectrometry. The X-ray powder diffraction pattern for the title compound was analyzed and found to be crystallized in an orthorhombic system with space group P212121 (No. 19) and refined unit-cell parameters a = 8.6415(8) Å, b = 12.679(2) Å, c = 17.601(2) Å, and V = 1928.4(2) Å3.

The structure of vitamin B 12 . IX. The crystal structure of cobyric acid, factor V 1 a

1971 ◽  
Vol 323 (1555) ◽  
pp. 455-480 ◽  
Keyword(s):  
Electron Density ◽  
Cobalt Atom ◽  
Crystallographic Analysis ◽  
Monoclinic Space Group ◽  
Factor V ◽  
X Ray ◽  
Cobyric Acid ◽  
The One ◽  
The Individual ◽  
Phase Angles

The structure of cobyric acid (factor V 1 a ), the aquocyanide of the natural nucleus of the B 12 vitamins, has been determined by X-ray crystallographic analysis. The crystals are monoclinic, space group, P2 1 ; the asymmetric unit has the contents, C 46 H 66 O 9 N 11 Co. 11H 2 O. The intensities of the X-ray spectra recorded with CuK α radiation were measured visually; they showed marked intensity differences between kkl and kkl reflexions due to anomalous dispersion, which permitted the calculation of phase angles for 1994 reflexions; the ambiguity in phase angle determination from the differences was resolved by choosing the one nearer to the phase of the cobalt atom. The first electron density map obtained revealed the structure almost completely. It has been refined by successive structure factor and difference electron density maps and block diagonal least squares calculations; in the later stages adjustments were made to the individual observed F values, 6188 reflexions in all. Many details of the geometry of the cobyric acid nucleus and of the attached side chains are well defined; one acetamide group, that on ring B, is rotated from its usual position to make a hydrogen bonded contact with a water molecule attached to the cobalt atom.

Conformational analysis of the bicyclo - [4.4.1]undecan-11-one ring system

2002 ◽  
Vol 80 (3) ◽  
pp. 245-249
Author(s):  
Masood Parvez ◽  
Ted S Sorensen ◽  
Fang Sun
Keyword(s):  
Conformational Analysis ◽  
Symmetry Plane ◽  
Ring System ◽  
Line Broadening ◽  
X Ray ◽  
The One ◽  
Effective Development ◽  
System 1 ◽  
C Nmr ◽  
Dibromo Derivative

The first conformational analysis of a bicyclo[4.4.1]undecan-11-one system (1) is presented. Based on low-temperature 13C NMR line-broadening measurements and an X-ray structure of the 1,6-dibromo derivative (2), this ketone adopts a chiral conformation with approximate C2 symmetry about an axis containing the >C=0 bond. The observed NMR line-broadening results are consistent with a dynamic interchange of M and P enantiomeric C2 conformations, or expressed another way, the "effective" development of an additional Cs symmetry plane bisecting the molecule at right angles to the plane containing the one carbon bridge (overall average C2v symmetry). This process has a ΔH‡ barrier of 42 kJ mol–1 for ketone 1 (43 kJ mol–1 for 2).Key words: bicyclo[4.4.1]undecan-11-one, conformational analysis, NMR line broadening, X-ray structure, enantiomers.

X-Ray Structure Analysis and NMR Study of Sesquiterpene Lactone Hirsutolide

1995 ◽  
Vol 60 (2) ◽  
pp. 300-310 ◽  
Author(s):  
Urszula Rychłewska ◽  
Miloš Buděšínský ◽  
Halina Grabarczyk ◽  
Bohdan Drożdż ◽  
Miroslav Holub
Keyword(s):  
Crystal Structure ◽  
Nmr Spectra ◽  
Chair Conformation ◽  
Ring Conformation ◽  
X Ray ◽  
H Nmr ◽  
Nmr Study ◽  
Nmr Methods ◽  
The One ◽  
C Nmr

Hirsutolide, the C(8)-lactonized sesquiterpene of the heliangolide type has been studied by X-ray and NMR methods. In crystal the ten-membered ring conformation closely resembles the conformation observed in C(6)-lactonized heliangolides. This conformation, which can be described as a boat-chair is contrasted with the chair-chair conformation found in the crystals of other C(8)-lactonized heliangolide, scorpioidine. Broad signals in 1H and 13C NMR spectra indicated the conformation equilibrium in solution which was confirmed by observation of signals of two conformers (ca 3 : 1) in low temperature 1H NMR spectra. The major conformer is the one present in the crystal structure of hirsutolide and the minor conformer corresponds very likely to the one observed in the crystal structure of scorpioidine.

Synthesis, characterization, and solid-state polymerization of cross-conjugated octatetraynes

2012 ◽  
Vol 90 (11) ◽  
pp. 994-1014 ◽  
Author(s):  
Yuming Zhao ◽  
Thanh Luu ◽  
Guy M. Bernard ◽  
Tyler Taerum ◽  
Robert McDonald ◽  
...  
Keyword(s):  
Solid State ◽  
Crystallographic Analysis ◽  
Scanning Calorimetry ◽  
X Ray ◽  
R And D ◽  
X Ray Crystallography ◽  
Topochemical Polymerization ◽  
Pendent Groups ◽  
C Nmr

Two series of cross-conjugated 1,3,5,7-octatetraynes (1a–1l and 6a–6d) have been synthesized. UV–vis spectroscopic analysis shows that pendent groups connected to the cross-conjugated skeleton have little effect on the λmax energies, irrespective of whether the groups are electron withdrawing or donating. A number of the isolated products readily give crystals suitable for X-ray crystallography, and the solid-state structural properties of five derivatives (1k, 1l, 6a, 6c, and 6d) have been examined by X-ray crystallographic analysis. Parallel packing of the polyynes in the solid state indicates that four of the five samples are potentially suitable for topochemical polymerization, based on solid-state packing parameters θ, R, and d. Attempts to effect a solid-state reaction have been explored through UV–vis and γ-ray irradiation as well as thermal heating. The course of these reactions was monitored by differential scanning calorimetry (DSC) analysis, as well as UV–vis and solid-state 13C NMR spectroscopy (for 1d, 1j, 1k, and 6d), which offered evidence of polymer formation from these reactions. Structural determination of the product(s), however, remains elusive.

Michael-Michael Aldol Reaction of Chalcones with Cyanoacetylurea and Cyanoacetylpiperidine

1995 ◽  
Vol 60 (4) ◽  
pp. 594-604 ◽  
Author(s):  
Hani D. Tabba ◽  
Nidal M. Yousef ◽  
Mohammad M. Al-Arab
Keyword(s):  
Room Temperature ◽  
Reaction Products ◽  
One Pot ◽  
X Ray ◽  
X Ray Crystallography ◽  
Anhydrous Alcohol ◽  
One Pot Condensation ◽  
The One ◽  
Sodium Alkoxide ◽  
C Nmr

Several highly substituted cyclohexane derivatives were synthesized by the one-pot condensation of chalcones and cyanoacetylurea (2 : 1) using sodium alkoxide in anhydrous alcohol at room temperature. The structure of the reaction products was established by infrared, 1H and 13C NMR spectroscopy as well as by their elemental analysis. Single crystal X-ray crystallography shows the presence of the cyclohexane moiety.

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