Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Structure of 1,5-benzodiazepinones in the solid state and in solution: Effect of the fluorination in the six-membered ring.

ABSTRACT: Two novel tetrafluorinated 1,5-benzodiazepinones were synthesized and their X-ray structures determined. 6,7,8,9-Tetrafluoro-4-methyl-1,3-dihydro-2H-1,5-benzodiazepin-2-one crystallizes in the monoclinic P21/c space group and 6,7,8,9-tetrafluoro-1,4-dimethyl-1,3-dihydro-2H-1,5-benzodiazepin-2-one in the triclinic P-1 space group. Density functional theory studies at the B3LYP/6-311++G(d,p) level were carried out on these compounds and on four non-fluorinated derivatives, allowing to calculate geometries, tautomeric energies and ring-inversion barriers, that were compared with the experimental results obtained by static and dynamic NMR in solution and in solid state.

SUBMITTER: Perez-Torralba M

PROVIDER: S-EPMC3817505 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Structure of 1,5-benzodiazepinones in the solid state and in solution: Effect of the fluorination in the six-membered ring.

Pérez-Torralba Marta M Claramunt Rosa M RM Angeles García M M López Concepción C Torralba M Carmen MC Rosario Torres M M Alkorta Ibon I Elguero José J

Beilstein journal of organic chemistry 20131021

Two novel tetrafluorinated 1,5-benzodiazepinones were synthesized and their X-ray structures determined. 6,7,8,9-Tetrafluoro-4-methyl-1,3-dihydro-2H-1,5-benzodiazepin-2-one crystallizes in the monoclinic P21/c space group and 6,7,8,9-tetrafluoro-1,4-dimethyl-1,3-dihydro-2H-1,5-benzodiazepin-2-one in the triclinic P-1 space group. Density functional theory studies at the B3LYP/6-311++G(d,p) level were carried out on these compounds and on four non-fluorinated derivatives, allowing to calculate ge ...[more]

PMID: 24204428

Similar Datasets

Are Non-Six-Membered Ring Defects Formed in Single-Walled Carbon Nanotubes Treated by a Fluorination-Defluorination Process?

Project description:Single-walled carbon nanotubes (SWCNTs) modified by introducing non-six-membered ring defects, such as five- and seven-membered rings, have attracted considerable attention because their conductivity is enhanced by increasing the electronic density of states at the Fermi energy level. However, no preparation method exists to efficiently introduce non-six-membered ring defects into SWCNTs. Herein, we attempt to introduce non-six-membered ring defects into SWCNTs by defect rearrangement of the nanotube framework using a fluorination-defluorination process. Defect-introduced SWCNTs were fabricated from SWCNTs fluorinated at 25 °C for different reaction times. Their structures were evaluated, and their conductivities were measured by operating a temperature program. Structural analysis of the defect-induced SWCNTs using X-ray photoelectron spectroscopy, Raman spectroscopy, high-resolution transmission electron microscopy, and visible-near-infrared spectroscopy did not reveal the presence of non-six-membered ring defects in the SWCNTs but indicated the introduction of vacancy defects. Meanwhile, conductivity measurements performed by operating a temperature program showed that the defluorinated SWCNTs prepared from SWCNTs fluorinated for 3 min (deF-RT-3m) exhibited decreased conductivity owing to the adsorption of water molecules to non-six-membered ring defects, thereby implying the possibility of non-six-membered ring defects being introduced into deF-RT-3m.

| S-EPMC10056250 | biostudies-literature

Six-membered-ring inorganic materials: definition and prospects.

Project description:The six-membered ring (SMR) is a common structure unit for numerous material systems. These materials include, but are not limited to, the typical two-dimensional materials such as graphene, h-BN, and transition metal dichalcogenides, as well as three-dimensional materials such as beryllium, magnesium, MgB2 and Bi2Se3. Although many of these materials have already become 'stars' in materials science and condensed-matter physics, little attention has been paid to the roles of the SMR unit across a wide range of compositions and structures. In this article, we systematically analyze these materials with respect to their very basic SMR structural unit, which has been found to play a deterministic role in the occurrence of many intriguing properties and phenomena, such as Dirac electronic and phononic spectra, superconductivity and topology. As a result, we have defined this group of materials as SMR inorganic materials, opening up a new perspective on materials research and development. With their unique properties, SMR materials deserve wide attention and in-depth investigation from materials design, new physical discoveries to target-wizard applications. It is expected that SMR materials will find niche applications in next-generation information technology, renewable energy, space, etc.

| S-EPMC8294346 | biostudies-literature

Synthesis, Solution and Solid State Structure of Titanium-Maltol Complex.

Project description:The reaction of Cp(2)TiCl(2) with two equivalents of maltol (3-hydroxy-2-methyl-4-pyrone) in water, at room temperature and pH of 5.4, leads to a complete replacement of Cp and chloride ligands affording, Ti(maltolato)(2)(OH)(2.) The complex has been characterized by IR, NMR and ESI-MS spectroscopic and cyclic voltammetry methods. In DMSO-d(6) solution, the complex shows two isomers in a ratio of 4:1, in which one OH signal can be identified per isomer. This suggests that in solution the complex is monomeric, most likely a chiral cis-Ti(maltolato)(2)(OH)(2) and trans-Ti(maltolato)(2)(OH)(2). The monomeric nature of the complex (in water/methanol 1:1) was verified by ESI-MS spectroscopy, showing a parent peak at 329 m/z. Electrochemical behavior of Ti(maltolato)(2)(OH)(2) using cyclic voltammetry experiments showed the complex undergoes irreversible reduction in aprotic solvents. In D(2)O solution, at pH of 8.4, the (1)H NMR spectrum of the complex shows a mixture of monomer and tetramer Ti(IV)-maltol complexes in a ratio of 1:1. The crystallization of Ti(maltolato)(2)(OH)(2) at pH of 8.4 leads to the formation of [Ti(4)(maltolato)(8)(μ-O(4))]•18H(2)O. A single crystal of [Ti(4)(maltolato)(8)(μ-O(4))]•18H(2)O was analyzed by X-ray diffraction methods. The complex crystallizes in a monoclinic space group P2(1)/c with a = 12.617(4) Å, b = 24.058(8) Å, c = 22.686(7) Å, β= 97.678(4)° and V = 6824(4) Å(3) for Z = 4. Solid state structure determination of the Ti-maltol complex showed to be tetrameric, containing two bridging oxides (in cis position) and two bidentate maltol ligands per titanium in a pseudo-octahedral coordination geometry.

| S-EPMC1948875 | biostudies-literature

Rhodium-catalyzed ring expansion of cyclopropanes to seven-membered rings by 1,5 C-C bond migration.

Project description: Not available

| S-EPMC3329940 | biostudies-literature

Membrane Protein Structure Determination and Characterisation by Solution and Solid-State NMR.

Project description:Biological membranes define the interface of life and its basic unit, the cell. Membrane proteins play key roles in membrane functions, yet their structure and mechanisms remain poorly understood. Breakthroughs in crystallography and electron microscopy have invigorated structural analysis while failing to characterise key functional interactions with lipids, small molecules and membrane modulators, as well as their conformational polymorphism and dynamics. NMR is uniquely suited to resolving atomic environments within complex molecular assemblies and reporting on membrane organisation, protein structure, lipid and polysaccharide composition, conformational variations and molecular interactions. The main challenge in membrane protein studies at the atomic level remains the need for a membrane environment to support their fold. NMR studies in membrane mimetics and membranes of increasing complexity offer close to native environments for structural and molecular studies of membrane proteins. Solution NMR inherits high resolution from small molecule analysis, providing insights from detergent solubilised proteins and small molecular assemblies. Solid-state NMR achieves high resolution in membrane samples through fast sample spinning or sample alignment. Recent developments in dynamic nuclear polarisation NMR allow signal enhancement by orders of magnitude opening new opportunities for expanding the applications of NMR to studies of native membranes and whole cells.

| S-EPMC7697852 | biostudies-literature

Solution-Deposited Solid-State Electrochromic Windows.

Project description:Commercially available electrochromic (EC) windows are based on solid-state devices in which WO3 and NiOx films commonly serve as the EC and counter electrode layers, respectively. These metal oxide layers are typically physically deposited under vacuum, a time- and capital-intensive process when using rigid substrates. Herein we report a facile solution deposition method for producing amorphous WO3 and NiOx layers that prove to be effective materials for a solid-state EC device. The full device containing these solution-processed layers demonstrates performance metrics that meet or exceed the benchmark set by devices containing physically deposited layers of the same compositions. The superior EC performance measured for our devices is attributed to the amorphous nature of the NiOx produced by the solution-based photodeposition method, which yields a more effective ion storage counter electrode relative to the crystalline NiOx layers that are more widely used. This versatile method yields a distinctive approach for constructing EC windows.

| S-EPMC6277218 | biostudies-literature

Ring expansion of alumoles with organic azides: selective formation of six-membered aluminum-nitrogen heterocycles.

Project description:Aside from simple Lewis acid-base chemistry, the reaction chemistry of aluminacyclopentadienes, which are commonly referred to as aluminoles or simply alumoles, remains relatively underdeveloped. To date, few attempts to extend their inherent insertion and cycloaddition reactivity to the construction of stable aluminum-containing heterocycles have been reported. Herein, we demonstrate the selective ring expansion of a cyclopentadienyl-substituted alumole with a series of organic azides to form unsaturated six-membered AlN heterocycles. Depending on the substituent on the azide, the reaction proceeds either with or without loss of dinitrogen, leading to incorporation of only the "NR" unit of the azide or the entire azo substituent into the periphery of the heterocycle. A deeper understanding of these ring expansion reactions is reached through computational studies, illustrating deviations in the mechanism as a function of the organic azide employed.

| S-EPMC7444475 | biostudies-literature

Regioselective Fluorination of Acenes: Tailoring of Molecular Electronic Levels and Solid-State Properties.

Project description:Optoelectronic properties of molecular solids are important for organic electronic devices and are largely determined by the adopted molecular packing motifs. In this study, we analyzed such structure-property relationships for the partially regioselective fluorinated tetracenes 1,2,12-trifluorotetracene, 1,2,10,12-tetrafluorotetracene and 1,2,9,10,11-pentafluorotetracene that were further compared with tetracene and perfluoro-tetracene. Quantum chemical DFT calculations in combination with optical absorption spectroscopy data show that the frontier orbital energies are lowered with the degree of fluorination, while their optical gap is barely affected. However, the crystal structure changes from a herringbone packing motif of tetracene towards a planar stacking motif of the fluorinated tetracene derivatives, which is accompanied by the formation of excimers and leads to strongly red-shifted photoluminescence with larger lifetimes.

| S-EPMC9305256 | biostudies-literature

Active-site structure of the thermophilic Foc-subunit ring in membranes elucidated by solid-state NMR.

Project description:FoF1-ATP synthase uses the electrochemical potential across membranes or ATP hydrolysis to rotate the Foc-subunit ring. To elucidate the underlying mechanism, we carried out a structural analysis focused on the active site of the thermophilic c-subunit (TFoc) ring in membranes with a solid-state NMR method developed for this purpose. We used stereo-array isotope labeling (SAIL) with a cell-free system to highlight the target. TFoc oligomers were purified using a virtual ring His tag. The membrane-reconstituted TFoc oligomer was confirmed to be a ring indistinguishable from that expressed in E. coli on the basis of the H(+)-translocation activity and high-speed atomic force microscopic images. For the analysis of the active site, 2D (13)C-(13)C correlation spectra of TFoc rings labeled with SAIL-Glu and -Asn were recorded. Complete signal assignment could be performed with the aid of the C(α)i+1-C(α)i correlation spectrum of specifically (13)C,(15)N-labeled TFoc rings. The C(δ) chemical shift of Glu-56, which is essential for H(+) translocation, and related crosspeaks revealed that its carboxyl group is protonated in the membrane, forming the H(+)-locked conformation with Asn-23. The chemical shift of Asp-61 C(γ) of the E. coli c ring indicated an involvement of a water molecule in the H(+) locking, in contrast to the involvement of Asn-23 in the TFoc ring, suggesting two different means of proton storage in the c rings.

| S-EPMC3907233 | biostudies-literature

Solution and Solid-State Characterization of PbSe Precursors.

Project description:The addition of lead to diphenyl diselenide in ethylenediamine (en) or pyridine (py) allowed for the observation of the solvento complexes, (en)Pb(SePh)2 or (py)2Pb(SePh)2, respectively. Performing this reaction in dimethyl sulfoxide and subsequent crystallization was found to afford Pb(SePh)2. Inductively coupled plasma optical emission spectroscopy revealed a 1:2 lead to selenium ratio for all three complexes. Nuclear magnetic resonance spectroscopy confirms that Pb(SePh)2 is readily solubilized by ethylenediamine, and electrospray ionization mass spectrometry supports the presence of Pb(SePh)2 moieties in solution. Single-crystal X-ray diffraction analysis of the pyridine adduct, (py)2Pb(SePh)2, revealed a seesaw molecular geometry featuring equatorial phenylselenolate ligands. Crystals of Pb(SePh)2 grown from dimethyl sulfoxide revealed one-dimensional polymeric chains of Pb(SePh)2. We believe that the lead(II) phenylselenolate complexes form via an oxidative addition reaction.

| S-EPMC7003517 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data