A Ring Destruction Approach to Some Benzo-Fused Medium-Sized Heterocycles by Means of Cyanogen-Bromide Under Solvolytic Conditions - X-Ray Structure of a '1h-2,6-Benzoxazecine-6-Carbonitrile and a '2h-3,6-Benzoxazecine-6-Carbonitrile Derivative

1986 ◽  
Vol 39 (6) ◽  
pp. 893 ◽  
Author(s):  
JB Bremner ◽  
CL Raston ◽  
GL Rowbottom ◽  
AH White ◽  
KN Winzenberg
Keyword(s):  
Molecular Structure ◽  
Tertiary Amine ◽  
Cyanogen Bromide ◽  
Crystal And Molecular Structure ◽  
X Ray ◽  
Concomitant Reduction ◽  
Heterocyclic Derivatives ◽  
Isoquinoline Derivatives ◽  
Ray Methods ◽  
Medium Ring

Reaction of the reduced pyrrolo [2,1-a] isoquinoline amine (1a) with cyanogen bromide in the presence of methanol gave the medium-ring cyanamide derivative 7,9,10-trimethoxy-2,3,4,5,6,7-hexahydro-1H-3- benzazonine-3-carbonitrile (2a). Analogous products were also obtained from reaction of the reduced 5H-oxazolo[2,3-a] isoquinoline , 2H- benzo [a] quinolizine , 2H,6H-[1,3] oxazino [2,3-a] isoquinoline and [1,4] oxazino [3,4-a] isoquinoline derivatives (1b-e), whereas the reduced 3H-oxazolo[4,3-a] isoquinoline and 5H-oxazolo[2,3-a] isoquinoline derivatives (1f) and (8) gave 1-(2,4-dioxapentyl)-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline-2-carbonitrile (5a) and N-[2-(2-benzoyl-4,5-dimethoxyphenyl)ethyl]-N- methylcyanamide (9) respectively, the latter in low yield. The medium-sized heterocyclic derivatives (2f-h) were also obtained from cyanogen -bromide-mediated water solvolysis reactions of (1a), (1c) and (1e). The cyanamides (2a-h), (5a) and (9) have been converted into the respective tertiary amine derivatives (3a- h), (5c) and (11), with concomitant reduction of the carbonyl group in the last case. The crystal and molecular structure of 1,10,11- trimethoxy-3,4,5,6,7,8-hexahydro-1H-2,6-benzoxazecine-6-carbonitrile (2d) and 1-hydroxy-10,11-dimethoxy-1,4,5,6,7,8-hexahydro-2H-3,6- benzoxazecine-6-carbonitrile (2h) have been determined by single- crystal X-ray methods.

Preparation of Thieno[3,2-e][1,2]oxazepine, Thieno and [1]Benzothieno-[3,2-g][1,4]oxazonine, and 5H-Thieno and 1H-[1]Benzothieno-[3,2-h][1,5]oxazecine Derivatives by Ring Expansion Methods. X-Ray Crystal Structure of 1-Phenyl-1,3,4,5,6,7-hexahydro[1]benzothieno-[3,2-g][1,4]oxazonine-5-carbonitrile

1988 ◽  
Vol 41 (12) ◽  
pp. 1815 ◽  
Author(s):  
JB Bremner ◽  
EJ Browne ◽  
LM Engelhardt ◽  
CS Greenwood ◽  
AH White
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Tertiary Amine ◽  
Cyanogen Bromide ◽  
Crystal And Molecular Structure ◽  
Ring Expansion ◽  
Standard Methods ◽  
X Ray ◽  
Medium Ring

10-Phenyl-4,5,6,7,8,10-hexahydrothieno[3,2-g][1,4]oxazonine-6-carbonitrile (6a) and 11-phenyl-4,6,7,8,9,11-hexahydro-5H-thieno[3,2-h][1,5]oxazecine-6-carbonitrile (7a) were prepared in moderate yields by cyanogen bromide-induced ring expansion of tetrahydrothieno [2,3- c] pyridinylalkanol precursors (4a) and (5a), respectively. 1-Phenyl-1,3,4,5,6,7-hexahydro[1]- benzothieno [3,2-g][1,4]oxazonine-5-carbonitrile (6b) and 1-phenyl-3,4,5,6,7,8-hexahydro-1H- [1] benzothieno [3,2-h][1,5]oxazecine-6-carbonitrie (7b) were similarly prepared from the [1] benzothieno [2,3-c] pyridinylalkanol precursors (4b) and (5b). The medium-ring cyanamides (6b) and (7b) were converted by standard methods into their N-methyl analogues (8b) and (9b). 6-Methyl-8-phenyl-4,5,6,8-tetrahydrothieno[3,2-e][1,2] oxazepine (13) was prepared by thermal Meisenheimer rearrangement of the corresponding tertiary amine N-oxide (12). The compounds (6a, b), (7a, b) and (13) are each the first reported examples of new heterocyclic systems. The crystal and molecular structure of (6b) has been determined by X-ray crystallographic methods.

Synthesis of Some Thieno Analogs of the Protoberberine and Protopine Skeletons. X-Ray Crystal Structure of 9,10-Dimethoxy-5-methyl-4,5,6,7,12,13-hexahydrothieno[3,2-e][3]benzazeci n-12-one

1988 ◽  
Vol 41 (1) ◽  
pp. 111 ◽  
Author(s):  
JB Bremner ◽  
EJ Browne ◽  
LM Engelhardt ◽  
GS James ◽  
AH White
Keyword(s):  
Molecular Structure ◽  
Cyanogen Bromide ◽  
Methyl Ketone ◽  
Functional Group ◽  
Crystal And Molecular Structure ◽  
Major Product ◽  
Ring System ◽  
X Ray ◽  
A Minor ◽  
Ray Methods

The preparation of the tetracyclic derivatives, (5) and (11), thienanalogues of the tetrahydroprotoberberine alkaloids, is described. Cyanogen bromide-induced water solvolysis of these isomeric compounds proceeded by different routes. 9,10-Dimethoxy-4,7,12,12a- tetrahydro-5H-benzo[g] thieno [3,2-a] quinolizine (11) under these conditions gave as the major product 4-(2-hydroxymethyl-4,5- dimethoxybenzyl )-4,5,6,7-tetrahydrothieno[3,2-c]pyridine-5- carbonitrile (12); no azecino derivatives were detected. By contrast such cleavage of 2,3-dimethoxy-5,8,12,12a-tetrahydro-6H- benzo [a] thieno [3,2-g] quinolizine (5) gave a major solvolytic ring- expanded product, 12-hydroxy-9,10-dimethoxy-4,5,6,7,12,13- hexahydrothieno [3,2-e][3]benzazecine-5-carbonitrile (15), and a minor elimination product, (E)-9,10-dimethoxy-4,5,6,7-tetrahydrothieno[3,2- e][3]benzazecine-5-carbonitrile (16). These last two compounds are examples of a new tricyclic ring system. From functional group interconversions of (15) was derived the N- methyl ketone (18), the first thieno analogue of the protopine alkaloid system. The crystal and molecular structure of this compound, 9,10-dimethoxy-5-methyl-4,5,6,7,12,13-hexahydrothieno[3,2-e][3] benzazecin - 12-one (18), has been determined by single-crystal X-ray methods.

Chalkogenolat-Ionen und ihre Derivate, V Kristall- und Molekülstruktur von 2.8-Dimethyldibenzo [c.g] [1.2.5.6] tetrathiacyclooktadien, einem Oxidationsprodukt von 4-Methylbenzol-1.2-dithiol/Chalcogenolates and their Derivatives, V Crystal and Molecular Structure of 2.8-Dimethyldibenzo[c,g][1,2,5,6]tetrathiaocin, an Oxidation Product of 4-Methylbenzene-1,2-dithiol

1979 ◽  
Vol 34 (1) ◽  
pp. 48-51 ◽  
Author(s):  
Jürgen Kopf ◽  
Klaus von Deuten ◽  
Bahman Nakhdjavan ◽  
Günter Klar
Keyword(s):  
Molecular Structure ◽  
Dihedral Angle ◽  
Oxidation Product ◽  
Crystal And Molecular Structure ◽  
X Ray ◽  
The Mean ◽  
Ray Methods ◽  
Anti Form

Abstract The structure of 2,8-dimethyldibenzo[c,g][1,2,5,6]tetrathiaocin (1b) has been determined by X-ray methods and discussed in connection with the preferred conformations of diaryl disulfides. The compound has the anti-form I. The SS-distance is 205.8 pm, the mean CSS-angle 104.1°, and the CSS/SSC-dihedral angle 111.1°.

The Meisenheimer rearrangement in heterocyclic synthesis. II. Synthesis and X-ray crystal structure of a tetrahydro-1H-2,3-benzoxazocine and preparation of a hexahydro-2,3-benzoxazonine

1980 ◽  
Vol 33 (6) ◽  
pp. 1323 ◽  
Author(s):  
JB Bremner ◽  
EJ Browne ◽  
PE Davies ◽  
CLWAH Raston
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Acetic Acid ◽  
Crystal And Molecular Structure ◽  
Phosphorus Oxychloride ◽  
Crystallographic Analysis ◽  
Heterocyclic Synthesis ◽  
Reaction Conditions ◽  
X Ray ◽  
Heterocyclic Derivatives

The heterocyclic derivatives, 8,9-dimethoxy-3-methyl-1-phenyl-3,4,5,6- tetrahydro-1H-2,3-benzoxazocine(3a) and 9,10-dimethoxy-3-methyl-1- phenyl-1,3,4,5,6,7-hexahydro-2,3-benzoxazonine (3b),examples of two new ring systems, have been prepared by Meisenheimer rearrangement of the corresponding 2-benzazepine and 2-benzazocine N-oxide derivatives (2a) and (2b). The Bischler-Napieralski-type cyclization reaction was used in the preparation of the tertiary amine precursors of these N-oxides reaction conditions for the cyclization were critical and phosphorus oxychloride in refluxing butanenitrile was found to give the best yields of the seven- or eight-membered cyclic imine intermediates. Reductive cleavage of the benzoxazocine derivative (3a) with zinc in acetic acid followed by N-methylation gave the expected product, [2-{3- (dimethylamino)propyl}-4,5-di-methoxyphenyl]phenylmethanol (12). The crystal and molecular structure of (3a) has been determined by X-ray crystallographic analysis.

Derivatives of the Benzo[5,6]cyclohepta[1,2,3-Cd]thieno[3,2-C]pyridine System. X-Ray Crystal Structure of 8,9-Dimethoxy-1,2,3,6,11,11a-hexahydrobenzo[5,6]cyclohepta[1,2,3-Cd]thieno[3,2-C]pyridine-1-carbonitrile

1988 ◽  
Vol 41 (4) ◽  
pp. 575 ◽  
Author(s):  
JB Bremner ◽  
EJ Browne ◽  
LM Engelhardt ◽  
BA Hyland ◽  
GS James ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Cyanogen Bromide ◽  
Heterocyclic System ◽  
Crystal And Molecular Structure ◽  
Ring Cleavage ◽  
Methyl Derivative ◽  
X Ray ◽  
Derivatives Of ◽  
By Products

During attempts to prepare 9,10-dimethoxy-4,7,12,12a-tetrahydro-5H- benzo [g] thieno [3,2-a] quinolizine (1), and subsequent cyanogen bromide- induced ring cleavage of this tetracyclic base, two by-products were isolated. The preparations of these two compounds are described, and their structures elucidated as 8,9-dimethoxy-1,2,3,6,11,11a-hexahydrobenzo [5,6] cyclohepta [1,2,3-cd] thieno [3,2-c]pyridine (5a), and its 1-carbonitrile derivative (5b). An N-methyl derivative (5c) has been prepared from (5a). These products (5) are the first examples of a new heterocyclic system. The crystal and molecular structure of the cyanamide (5b) has been determined by X-ray crystallographic methods.

Synthesis of 2,3-Dihydro-1,4,5-benzodioxazocines. X-ray structure of 6-Phenyl-2,3-dihydro-1,4,5-benzodioxazocine

1983 ◽  
Vol 36 (12) ◽  
pp. 2555 ◽  
Author(s):  
EJ Browne ◽  
LM Engelhardt ◽  
AH White
Keyword(s):  
Molecular Structure ◽  
Single Crystal ◽  
Crystal And Molecular Structure ◽  
Ring System ◽  
Cyclic Dimer ◽  
X Ray ◽  
Ray Methods ◽  
By Products

Derivatives (6a-c) of the 1,4,5-benzodioxazocine ring system have been prepared in low-to-moderate yields by hydrazinolysis of {2-[2-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)oxyethyloxy]aryl}phenylmethanones(5a-c), and cyclization of the products at pH c. 4. Only in the case of (6b) was a trace of a cyclic dimer (7b) detected, in contrast to the analogous preparations of the 2H-1,5,6-benzodioxazonine derivatives (1a-c) where 18-membered cyclic dimers (8a-c) formed as by-products. The crystal and molecular structure of 6-phenyl-2,3-dihydro-1,4-5-benzodioxazocine (6a) has been determined by single-crystal X-ray methods.

Radical Cation Salts of an Unsymmetrical BEDT-TTF Derivative: Molecular Structure and Physical Properties of (DIMET*)2CIO4 X THF

1985 ◽  
Vol 40 (12) ◽  
pp. 1703-1710 ◽  
Author(s):  
R. Heid ◽  
H. Endres ◽  
H. J. Keller
Keyword(s):  
Molecular Structure ◽  
Electrical Conductivity ◽  
Physical Properties ◽  
Crystal And Molecular Structure ◽  
Average Charge ◽  
Two Dimensional ◽  
X Ray ◽  
Radical Cation Salts ◽  
Solvent Molecules ◽  
Ray Methods

Abstract 4.5-Dimethyl-4'.5'-ethylenedithiolotetrathiafulvalene (DIMET) was obtained by reacting 4.5- ethylenedithiolo-1.3-dithioliumtetrafluoroborate with 4.5-dimethyl- 1.3-dithiolium-tetrafluoroborate in the presence of diisopropylethylamine or triethylamine. Electrocrystallization of this donor in different solvents like dichloromethane or tetrahydrofurane (THF) and with varying supporting electrolytes, like tetrabutylammonium hexafluorophosphate, triiodide, nitrate, perrhenate or perchlorate, results in a large number of well crystallizing compounds. The crystal and molecular structure of one of the isolated solids was elucidated by X-ray methods. (C10)H10S6)2CIO4 x C4H8O, Mr = 816.66, is triclinic, P1̄ , a = 6.731(5), b - 7.632(3), c = 33.32(3) Å , α = 96.53(5), β = 92.99(6), γ = 103.13(5)°, V - 1650.7 Å3, Z = 2, dc = 1.64 gem-3, final Rw = 0.077 for 1844 observed independent reflections. Sheets of cations with an average charge of 1/2+ are separated by sheets of anions and THF solvent molecules. Intermolecular S···S contacts result in two-dimensional physical properties. Electrical conductivity and thermopower measurements indicate two broad phase transitions at around 200 K and 80 K

Studies of the rhenium–oxygen bond. II. The crystal and molecular structure of µ-oxobis(cis-dichloro-cis-di(pyridine)-trans-oxorhenium(V)), ORe(C5H5N)2Cl2ORe(C5H5N)2Cl2O

1978 ◽  
Vol 56 (2) ◽  
pp. 179-188 ◽  
Author(s):  
Colin James Lyne Lock ◽  
Graham Turner
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Single Crystal ◽  
Least Squares ◽  
Crystal And Molecular Structure ◽  
The Other ◽  
Full Matrix ◽  
X Ray ◽  
Ray Methods ◽  
Oxygen Bond

The crystal structure of µ-oxobis(cis-dichloro-cis-di(pyridine)-trans-oxorhenium(V)), ORe(C5H5N)2Cl2•O•Re(C5H5N)2Cl2O bas been studied by single crystal X-ray methods. The crystals were orthorhombic with lattice parameters a = 15.367(2), b = 10.283(2), c = 16.685(2) Å. The space group was Pna21 and there were four formula weights per unit cell. A total of 3339 reflections, of which 2990 were observed, were examined, and the structure refined by full matrix least squares (treating the pyridine rings as groups) to an R2 value of 0.0449. The dimer had a roughly rectilinear O—Re—O—Re—O backbone with pairs of chlorine atoms and pyridine molecules arranged cis in each half of the dimer. The two halves of the dimer were arranged such that the pairs of cis atoms in one half were rotated about the Re(1)–Re(2) axis almost 113 ° when compared to the corresponding pair in the other half. Important bond lengths (Re—O(terminal), 1.715(16), 1.764(16); Re—O(bridging), 1.943(16), 1.903(16); Re—Cl, 2.356(5)–2.390(5); Re—N, 2.116(16)–2.180(16)) were close to previously observed values. The molecule was markedly disturbed from the idealized structure and this was caused by intramolecular non-bonded interactions.

Nucleophilic Displacements of Imidazoles. I. Oxygen, Nitrogen and Carbon Nucleophiles

1987 ◽  
Vol 40 (8) ◽  
pp. 1399 ◽  
Author(s):  
S Kulkarni ◽  
MR Grimmett ◽  
LR Hanton ◽  
J Simpson
Keyword(s):  
Molecular Structure ◽  
Crystal And Molecular Structure ◽  
Direct Methods ◽  
X Ray ◽  
Carbon Nucleophiles ◽  
Nucleophilic Displacement ◽  
Ray Methods

4(5)- Bromo - and - iodo-imidazoles, activated by an adjacent nitro substituent, undergo nucleophilic displacement with methoxide, phenoxide , cyclic secondary chines and cyanide. The regiochemistry of the reactions of 5-iodo-4-nitroimidazole with methoxide has been confirmed by spectroscopic and X-ray methods, and a number of erroneous structures from the literature have been revised. Some apparently anomalous reactions of methoxide with 5-halo-1,2-dimethyl-4- nitroimidazoles, and of cyanide with 4-halo-1-methyl-5-nitroimidazole have been noted. The crystal and molecular structure of 5-methoxy-1-methyl-4-nitroimidazole has been determine: by direct methods. Crystals are monoclinic, P21/c, a 10.929(3), b 8 899(2), c 7.290(2) �; β 92.87(2)�; Z 4. The structure was refined to R = 0.095 for 818 reflections (I > 2σI).

Crystal structures of medium ring compounds. Part III. The crystal and molecular structure of trans-anti-trans-4,5:9,10-biscyclohexano-1,3,6,8-tetraoxecane

1979 ◽  
Vol 57 (16) ◽  
pp. 2154-2158 ◽  
Author(s):  
Aris Terzis ◽  
T. Bruce Grindley
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Crystal And Molecular Structure ◽  
Chair Conformation ◽  
Membered Ring ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ring Compounds ◽  
R Value ◽  
Medium Ring

The crystal structure of trans-anti-trans-4,5:9,10-biscyclohexano-1,3,6,8-tetraoxecane (3) has been determined by X-ray diffraction. The crystals are monoclinic, a = 11.919(3), b = 17.330(7), c = 7.019(2) Å, β = 98.91(1)°, P21/c, with Z = 4. The structure was solved by application of the tangent formula and refined by large block least squares to a final R value of 0.060 (Rw = 0.058).The ten-membered ring is present in the crystal in a twist-chair-boat-chair conformation — one which has been calculated to be relatively unstable for cyclodecane. Possible reasons why 3 adopts this conformation are discussed.

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