Open chain nitrogen compounds. Part XI. 3,7-Bis(arylazo)-1,3,5,7-tetraazabicyclo[3,3,1]nonanes: the reaction of diazonium ions with ammonia–formaldehyde mixtures

1986 ◽  
Vol 64 (8) ◽  
pp. 1567-1572 ◽  
Author(s):  
Robert D. Singer ◽  
Keith Vaughan ◽  
Donald L. Hooper
Keyword(s):  
Condensation Product ◽  
Chair Conformation ◽  
Chain Structure ◽  
Open Chain ◽  
Bicyclic System ◽  
Mannich Condensation ◽  
Diazonium Ions ◽  
Buffer Mixture ◽  
Aqueous Mixture ◽  
Slow Decomposition

Reaction of a series of diazonium salts with either hexamine or an aqueous mixture of ammonia–formaldehyde affords 3,7-bis(arylazo)-1,3,5,7-tetraazabicyclo[3,3,1]nonanes; several new examples of this novel class of bicycloheterocycle have been prepared and characterized. Analysis of the low-temperature nmr spectra of one compound in this series shows that the bicyclic system prefers the chair–chair conformation. The bis(arylazo)tetraazabicyclononanes, which are surprisingly stable in aqueous buffer compared to analogous triazenes of open-chain structure, do undergo slow decomposition at slightly acidic pH in an acetone–buffer mixture. The apparent product of this decomposition is the arylamine, which is observed as the Mannich condensation product, ArNH•CH2CH2COCH3.

scholarly journals Crystal structure and Hirshfeld surface analysis of 3-octyl-4-oxo-2,6-bis(3,4,5-trimethoxyphenyl)piperidinium chloride

2018 ◽  
Vol 74 (7) ◽  
pp. 931-934
Author(s):  
Rubina Siddiqui ◽  
Urooj Iqbal ◽  
Zafar Saeed Saify ◽  
Shammim Akhter ◽  
Sammer Yousuf
Keyword(s):  
Surface Analysis ◽  
Crystal Packing ◽  
Condensation Reaction ◽  
Chair Conformation ◽  
Hirshfeld Surface ◽  
Hirshfeld Surface Analysis ◽  
One Pot ◽  
Compound C ◽  
Mannich Condensation ◽  
Centrosymmetric Dimers

The title compound, C31H46NO7 +·Cl−, was synthesized by a one-pot Mannich condensation reaction. In the molecule, the piperidinone ring adopts a chair conformation, and the trimethoxy-substituted benzene rings and octyl chain are arranged equatorially. In the crystal, centrosymmetric dimers are linked into layers parallel to (011) by N—H...Cl and C—H...Cl hydrogen bonds. A Hirshfeld surface analysis indicates that the most important contributions for the crystal packing are O...H (20.5%) interactions followed by C...H (7.8%), Cl...H (5.5%), C...C (1.2%), C...O (0.5%) and Cl...O (0.4%) interactions.

(1R*,5R*,7R*,8S*)-3-(3,4-Dihydroxybenzoyl)-4-hydroxy-8-methyl-1,5,7-tris(3-methyl-2-butenyl)-8-(4-methyl-3-pentenyl)bicyclo[3.3.1]non-3-ene-2,9-dione

2007 ◽  
Vol 63 (3) ◽  
pp. o1282-o1284 ◽  
Author(s):  
Bruno Ndjakou Lenta ◽  
Diderot Tchamo Noungoue ◽  
Krishna Prasad Devkota ◽  
Patrice Aime Fokou ◽  
Silvere Ngouela ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Medicinal Plant ◽  
Chair Conformation ◽  
The Other ◽  
Aryl Group ◽  
One Dimensional ◽  
Compound C ◽  
Bicyclic System ◽  
Symphonia Globulifera

The title compound, C38H50O6, also known as guttiferone A, was isolated from the medicinal plant Symphonia globulifera. It is a benzophenone derivative where one aryl group is derivatized to give a bicyclic system which has two prenyl groups attached to the bridgehead. One of the cyclohexane rings in the bicyclic system is in a chair form, while the other has a distorted half-chair conformation. In addition to an intramolecular O—H...O hydrogen bond, intermolecular O—H...O hydrogen bonds link molecules into one-dimensional chains.

scholarly journals Crystal structure of sodium (1S)-D-lyxit-1-ylsulfonate

2016 ◽  
Vol 72 (5) ◽  
pp. 628-631
Author(s):  
Alan H. Haines ◽  
David L. Hughes
Keyword(s):  
Crystal Structure ◽  
Three Dimensional ◽  
Chain Structure ◽  
Zigzag Chain ◽  
Sugar Chain ◽  
Open Chain ◽  
Torsion Angles ◽  
Hydroxymethyl Group ◽  
Sodium Hydrogen ◽  
Group Form

The title compound, Na+·C5H11O8S−[systematic name: sodium (1S,2S,3S,4R)-1,2,3,4,5-pentahydroxypentane-1-sulfonate], is formed by reaction of D-lyxose with sodium bisulfite (sodium hydrogen sulfite) in water. The anion has an open-chain structure in which one of the oxygen atoms of the sulfonate residue, the S atom, the C atoms of the sugar chain and the O atom of the hydroxymethyl group form an essentially planar zigzag chain with the corresponding torsion angles lying between 179.80 (11) and 167.74 (14)°. A three-dimensional bonding network exists in the crystal structure involving hexacoordination of sodium ions by O atoms, three of which are provided by a single D-lyxose–sulfonate unit and the other three by two sulfonate groups and one hydroxymethyl group, each from separate units of the adduct. Extensive intermolecular O—H...O hydrogen bonding supplements this bonding network.

Gold(I) Complexes of Open-chain and Cyclic Di-secondary Amines

1997 ◽  
Vol 52 (2) ◽  
pp. 209-213 ◽  
Author(s):  
José M. López-de-Luzuriaga ◽  
Marcus Söldner ◽  
Annette Schier ◽  
Hubert Schmidbaur
Keyword(s):  
Hydrogen Bonding ◽  
Hydrogen Atom ◽  
Hydrogen Bonds ◽  
Chair Conformation ◽  
Secondary Amines ◽  
Binuclear Complexes ◽  
Open Chain ◽  
Piperazine Ring ◽  
Ethylene Bridge ◽  
Solvent Molecules

Abstract Treatment of N,N′-diisopropyl-ethylenediamine or 1,4-piperazine with two equivalents of [(Ph3P)Au]+ BF4- leads to binuclear complexes of the diamines: {[(Ph3P)Au]HN(iPro)NCH2-}22+ 2 BF4- (1) and {[(Ph3P)Au]HNCH2CH2}22+ 2 BF4- (2), respectively. In the products each quaternary ammonium center bears one gold ligand, one hydrogen atom and two alkyl substituents. The crystal structures of both compounds have been determined. Compound 1 contains discrete ion-triples. The ethylene bridge in the dications is in an unfolded conformation, with a crystallographic center of inversion, and allows for weak hydrogen bonding N-H--F [2.085 Å; N-H--F 169.2°] between the NH functions and the counterions. The existing distant contacts F--Au [3.599 Å] are probably less significant for the aggregation of the ion triples, but will contribute through Coulomb forces. Compound 2 crystallizes with two solvent molecules CH2CI2. The dication has a crystallographic center of inversion with the piperazine ring in a chair conformation and the gold atoms in equatorial positions. There are hydrogen bonds N-H--F [2.076 and 2.457 Å] between the dication and the anions which lead to the formation of ion-triples, with further contacts between the BF4- anions and the solvent molecules [C-H--F 2.340 and 2.446 Å].

The Lability of Sulfur Atoms in Vulcanization

1960 ◽  
Vol 33 (4) ◽  
pp. 1010-1014
Author(s):  
G. A. Blokh
Keyword(s):  
High Energy ◽  
Chain Structure ◽  
Elementary Sulfur ◽  
Open Chain ◽  
Isotope Method ◽  
Sulfur Containing ◽  
Unstable Intermediate ◽  
Sulfur Containing Compounds

Abstract The application of the isotope method to the investigation of the mechanism of the action of accelerator and vulcanizing agents has made it possible to look at this question in quite a new light. With the help of the isotope S it has been demonstrated that in the process of curing there takes place a continuous exchange of atoms of sulfur in the structure of the accelerators, and of elementary sulfur as a vulcanizing agent, with the formation of unstable intermediate compounds. The sulfur thus liberated undoubtedly has high energy, as a result of which it combines rapidly with the rubber. It must be remembered in this connection that the reacting elementary sulfur is an eight-membered S8 ring, while the sulfur liberated from the sulfur containing compounds has the open chain structure:

Structure of a condensation product of triethylaluminium and a multidentate open-chain amine

1990 ◽  
Vol 46 (6) ◽  
pp. 1110-1111
Author(s):  
F. Moise ◽  
W. T. Pennington ◽  
G. H. Robinson ◽  
S. A. Sangokoya
Keyword(s):  
Condensation Product ◽  
Open Chain

scholarly journals Sodium (1R)-D-glucit-1-ylsulfonate monohydrate

2012 ◽  
Vol 68 (4) ◽  
pp. m377-m378 ◽  
Author(s):  
Alan H. Haines ◽  
David L. Hughes
Keyword(s):  
Complex Cation ◽  
Three Dimensional ◽  
Addition Product ◽  
Chain Structure ◽  
Water Molecules ◽  
Open Chain ◽  
Carbon Chains ◽  
Molecular Anions ◽  
Dimensional Network ◽  
Cation Coordination

The title salt, Na+·C6H13O9S−·H2O, crystallizes with three independent cations, molecular anions and solvent water molecules in the asymmetric unit. This crystalline monohydrate addition product, formed by reaction of D-glucose and sodium hydrogen sulfite in water, forms a three-dimensional network through complex cation coordination and extensive intermolecular hydrogen bonding. Each of the independent molecules has an open-chain structure with the carbon chains adopting a sickle-like conformation, similar to that found in the potassium salt [Coleet al.(2001).Carbohydr. Res.335, 1–10], but there are significant differences in the patterns of complexation.

ChemInform Abstract: Stabilization of the Open-Chain Structure of D-Galacturonic Acid in a Dimeric Complex with Oxovanadium(IV).

ChemInform ◽  
1990 ◽  
Vol 21 (40) ◽  
Author(s):  
M. BRANCA ◽  
G. MICERA ◽  
D. SANNA ◽  
A. DESSI ◽  
H. KOZLOWSKI
Keyword(s):  
Galacturonic Acid ◽  
Chain Structure ◽  
Dimeric Complex ◽  
Open Chain

Infrared study of the self-association of water dissolved in 1,2-dichloroethane

1968 ◽  
Vol 46 (4) ◽  
pp. 567-570 ◽  
Author(s):  
C. Jolicoeur ◽  
A. Cabana
Keyword(s):  
Low Frequency ◽  
Solute Concentration ◽  
Chain Structure ◽  
Linear Increase ◽  
Small Frequency ◽  
Open Chain ◽  
Infrared Study ◽  
Frequency Shifts ◽  
Polymeric Species ◽  
Self Association

The infrared spectra, in the 3 micron region, of H2O or HDO dissolved in 1,2-dichloroethane are presented. Self-association of the solute molecules is revealed by the appearance of a shoulder on the low frequency side of the OH stretching bands of monomeric H2O or HDO. From the linear increase of the intensity of the shoulder with the third power of the solute concentration, it is inferred that trimers constitute the main polymeric species present in these solutions. The small frequency shifts of the OH stretching mode of trimeric water favors a cyclic rather than an open-chain structure. The observation of a single band for the trimer correlates with this last assertion.

scholarly journals 1-Deacetoxy-1-oxocaesalmin

2014 ◽  
Vol 70 (6) ◽  
pp. o662-o662
Author(s):  
Juan Feng ◽  
Jian-Long Zhang ◽  
Rong-Rong Zhang ◽  
Li-Jun Ruan ◽  
Ren-Wang Jiang
Keyword(s):  
Hydrogen Bonds ◽  
Title Compound ◽  
Furan Ring ◽  
Chair Conformation ◽  
Chain Structure ◽  
Membered Ring ◽  
Axis Direction ◽  
Compound C ◽  
A Chain

The title compound, C24H30O7, is a diterpenoid isolated from the seeds ofCaesalpinia minax. It consists of two cyclohexane rings (AandB), one unsaturated six-membered ring (C) and one furan ring (D). The stereochemistry of the ring junctures isA/B transandB/C trans. RingsAandBhave normal chair conformations whileCadopts a twisted half-chair conformation due to fusion to the furan ring which is planar [r.m.s. deviation = 0.0009 (2) Å]. In the crystal, hydroxyl O—H...Ocarbonylhydrogen bonds link the molecules into a chain structure extending along thea-axis direction.

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