Search results for "Oxide"
showing 10 items of 6424 documents
ChemInform Abstract: Multifunctional Poly(ethylene glycol)s
2011
In the rapidly evolving multidisciplinary field of polymer therapeutics, tailored polymer structures represent the key constituent to explore and harvest the potential of bioactive macromolecular hybrid structures. In light of the recent developments for anticancer drug conjugates, multifunctional polymers are becoming ever more relevant as drug carriers. However, the potentially best suited polymer, poly(ethylene glycol) (PEG), is unfavorable owing to its limited functionality. Therefore, multifunctional linear copolymers (mf-PEGs) based on ethylene oxide (EO) and appropriate epoxide comonomers are attracting increased attention. Precisely engineered via living anionic polymerization and d…
Über polymerisationen mit hilfe von redox-systemen
1951
Bei der durch Eisen-Redox-Systeme ausgelosten Polymerisation von Styrol und von Dimethylbutadien -2.3 wird die peroxydische Komponente (Diacylperoxyd) in die Makromolekule eingebaut. Es wird gezeigt, das bei der Polymerisation des Styrols mit Dibrombenzoylperoxyd-Eisenbenzoat-Benzoin die Zahl der eingebauten, markierten Endgruppen die gleiche ist wie bei der peroxydischen Polymerisation mit Di-Brombenzoylperoxyd. Dies spricht dafur, das auch die peroxydische Polymerisation durch Radikale ausgelost wird, die bei einer Redox-Reaktion zwischen Peroxyd und Monomerem entstehen. Fur das polymere Dimethylbutadien wurde nachgewiesen, das alle markierten Endgruppen, die bei der eisen-redox-katalysie…
Generalized synthesis of periodic surfactant/inorganic composite materials
1994
THE recent synthesis of silica-based mesoporous materials1,2 by the cooperative assembly of periodic inorganic and surfactant-based structures has attracted great interest because it extends the range of molecular-sieve materials into the very-large-pore regime. If the synthetic approach can be generalized to transition-metal oxide mesostructures, the resulting nanocomposite materials might find applications in electrochromic or solid-electrolyte devices3,4, as high-surface-area redox catalysts5 and as substrates for biochemical separations. We have proposed recently6 that the matching of charge density at the surfactant/inorganic interfaces governs the assembly process; such co-organizatio…
Reactions of Peroxides on Solid Surfaces
2014
This article describes the different roles that solid surfaces play in heterogeneous reactions involving peroxides, namely, (i) the solid surface interacts with the peroxide in the absence of any other substrate, (ii) the solid surface promotes the reaction activating either the peroxide or the substrate, (iii) the peroxide forms part of the solid active surface, and (iv) the substrate forms part of the active surface. The chapter covers reactions involving peroxides or discrete peroxydic transient species on solid surfaces or at solid–liquid and solid–gas interfaces, and provides general descriptions of different solid materials, details on reaction conditions, and synthetic procedures for…
ChemInform Abstract: Tandem Asymmetric Michael Reaction-Intramolecular Michael Addition. An Easy Entry to Chiral Fluorinated 1,4-Dihydropyridines.
2010
The sequential treatment of optically active sulfoxide (I) with fluorinated nitriles and alkyl propiolates affords (sulfinylmethyl)dihydropyridines of type (IV) as single diastereomers in most cases.
Direct pyrolysis in the mass spectrometer of aromatic polysulfonates and polythiosulfonates
1978
The thermal degradation mechanism of three aromatic polysulfonates and polythiosulfonates was investigated by direct pyrolysis in the ion source of a mass spectrometer. Thermal degradation reactions were followed directly by this method by detecting the thermal and electron impact induced fragments. The results obtained have provided evidence that sulfur dioxide extrusion from the polymer backbone takes place in these polymers above 300°C. The synthesis and molecular characterization of the polymers studied are reported in the text.
Theoretical Study of the Elimination Kinetics of Carboxylic Acid Derivatives in the Gas Phase. Decomposition of 2-Chloropropionic Acid
1997
The reaction mechanism for the decomposition of 2-chloropropionic acid in the gas phase to form hydrogen chloride, carbon monoxide, and acetaldehyde has been theoretically characterized. Analytical gradients have been used by means of AM1 and PM3 semiempirical procedures and ab initio methods at HF and DFT (BLYP) levels with the 6-31G** basis set. The correlation effects were also included by using the perturbational approach at the MP2 level with the 6-31G** and 6-31++G** basis sets and the variational approach at the CISD/6-31G** level and by means of MCSCF wave functions with a (6,6) complete active space and the 6-31G** basis set. The global potential energy surface has been studied, an…
(1aR,2aS,5aS,5bS)-Perhydro-4H-oxireno[3,4]cyclopenta[1,2-b]furan-4-one
2007
The structure of the title compound, C7H8O3, was determined in the course of our studies of the synthesis of cyclopenta[1,2-b]furan-4-one derivatives. The molecule has four chiral C atoms. The X-ray crystal structure analysis shows the compound to possess an epoxide group with an endo orientation with respect to the lactone group.
Mammalian Xenobiotic Epoxide Hydrolases
2002
Propane-1,3-diammonium molybdate
2019
The reaction between equimolar amounts of propane-1,3-diamine and molybdenum trioxide in water led to the formation of single crystals of the title salt, (C3H12N2)[MoO4]. The asymmetric unit is comprised of one propane-1,3-diammonium cation and one molybdate anion. The latter is isolated in the structure and has a slightly distorted tetrahedral configuration. An extensive network of N—H...O hydrogen bonds connects anions and cations, giving rise to a compact three-dimensional packing.