4437-52-9

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InChI:InChI=1/C6H12N2O2/c1-3-5(7-9)6(4-2)8-10/h7,9H,3-4H2,1-2H3/b6-5+

Upstream product

• 4437-51-8 3,4-hexanedione 
• 4984-85-4 propioin 

Relevant academic research and scientific papers

Binary copolymerization with catalytic chain transfer. A method for synthesizing macromonomers based on monosubstituted monomers

With appropriate choice of conditions, copolymerization of monosubstituted monomers [CH2=CHX: e.g., styrene, butyl acrylate (BA)] in the presence of small amounts of an α-methylvinyl monomer [CH 2=C(CH3)Y: e.g., α-methylstyrene (AMS), methyl methacrylate (MMA), methacrylonitrile (MAN)] and a cobaloxime as chain transfer catalyst provides a route to macromonomers that are composed largely of the monosubstituted monomer and yet have a chain end derived from the α-methylvinyl monomer (-CH2-C(=CH2)Y). The various factors (temperature, concentrations, type of cobaloxime, types of monomer) that influence molecular weight and end group purity and the importance of the various side reactions that may complicate the process are described. Macromonomer purity is enhanced by increasing the concentration of the α-methylvinyl monomer and reducing the cobaloxime concentration. It also depends on the structure of the cobaloxime, increasing in the series where the ligands are derived from dimethyl glyoxime 2R CN Ph. For styrene-AMS copolymerization, macromonomer purity (the fraction of AMS-derived ends) was enhanced by increasing the reaction temperature. For BA-AMS copolymerization, macromonomer purity was enhanced by decreasing the reaction temperature. However, it is necessary to use a high reaction temperature to limit the extent of macromonomer copolymerization that occurs as a side reaction at high monomer conversion. High purity, AMS terminal BA macromonomers can be prepared by BA-AMS copolymerization at 125°C with as little as 2 mol % AMS. We also show how the overall composition, molecular weight, and end group functionality of copolymers formed in the presence of a chain transfer agent can be predicted using classical statistics and point out some problems with previous treatments. Analytical expressions which describe zero conversion binary copolymerization in the presence of a transfer agent are derived and successfully applied to the above-mentioned system. The effective transfer constants of cobaloxime transfer catalysts are reported. Those observed in copolymerizations of vinyl and α-methylvinyl monomers are reduced with respect to values observed in homopolymerization of α-methylvinyl monomers because of reversible consumption of the cobalt complex as an adduct to the vinyl monomer. Transfer constants of macromonomers with AMS end groups in styrene polymerization at 120°C are in the range 0.11-0.15. At lower temperatures (80°C), macromonomer copolymerization dominates over chain transfer and the effective transfer constant is ～0.

Conformation of diethylglyoxime in uranyl complexes

New complexes of uranyl with diethylglyoxime have been synthesized and studied. A feature of these complexes is the tetradentate bridging coordination of the ligand in both cis- and trans-conformations. The structure of organic ligand C6H12N2O2 and binuclear complex (CN3H6)4[(UO2)2(C6H10N2O2)(CO3)(C2O4)2] ? H2O have been determined by X-ray diffraction.

Oxidation of: O -dioxime by (diacetoxyiodo)benzene: Green and mild access to furoxans

Furoxan has been widely used in the field of high energy density materials because of its excellent properties such as high density, high standard enthalpy of formation and high nitrogen content. However, its existing synthesis methods are still restricted by the problems of difficult substrate preparation and manual handling of hazardous reagents. Herein, we disclosed a mild oxidation strategy to efficiently obtain furoxan derivatives starting from readily available o-dioxime substrates. This reaction features high functional group tolerance and easy scale-up, and has excellent regioselectivity for specific nonsymmetric o-dioximes. This method greatly reduces the safety risk and simplifies the operation process, and means that diversified furoxan derivatives can be easily accessed, thus paving the way for the wide application of furoxan derivatives. This journal is

High-Throughput Screening of Earth-Abundant Water Reduction Catalysts toward Photocatalytic Hydrogen Evolution

Noble-metal photosensitizers and water reduction co-catalysts (WRCs) still present the highest activity in homogeneous photocatalytic hydrogen production. The search for earth-abundant alternatives is usually limited by the time required to screen new catalyst combinations; however, here, we utilize newly designed and developed high-throughput photoreactors for the parallel synthesis of novel WRCs and colorimetric screening of hydrogen evolution. This unique approach allowed rapid optimization of photocatalytic water reduction using the organic photosensitizer Eosin Y and the archetypal cobaloxime WRC [Co(GL1)2pyCl], where GL1 is dimethylglyoxime and py is pyridine. Subsequent combinatorial synthesis generated 646 unique cobalt complexes of the type [Co(LL)2pyCl], where LL is a bidentate ligand, that identified promising new WRC candidates for hydrogen production. Density functional theory (DFT) calculations performed on such cobaloxime derivative complexes demonstrated that reactivity depends on hydride affinity. Alkyl-substituted glyoximes were necessary for hydrogen production and showed increased activity when paired with ligands containing strong hydrogen-bond donors.

1,2-Dioximes in the Trofimov reaction

3,3′-Dimethyl-1,1′-divinyl-2,2′-dipyrrole was obtained during the reaction of 3,4-hexanedione dioximes with acetylene under pressure in the potassium hydroxide-DMSO system. In the case of 1,2-cyclohexanedione dioxime 2,2′-dipyrrole and 2-pyridyl- and 2-acylpyrroles were isolated. α-Benzil and α-furil dioximes give 3,4-diphenyl- and 3,4-di(2-furyl)-1,2,5-oxadiazoles respectively in addition to their mono- and divinyl derivatives. 2006 Springer Science+Business Media, Inc.