Search results for "Sulfoxide"
showing 10 items of 313 documents
Inhibitoren der Korrosion (12). Nachweis der Bildung von Sekundärinhibitoren mit Hilfe der „Spezifischen Keim-Methode” von Karagounis
1972
Verschiedene gut inhibierende Oniumsalze werden in saurer Losung an der Oberflache von Eisen reduziert. Die dabei entstehenden Sekundarprodukte sind selbst gute Inhibitoren und bilden auf der Metalloberflache dunne Schichten. Diese haben unterschiedliche Dicke: Dibenzylsulfoxid bildet in kurzer Zeit bis zu 20 Molekullagen, einige quaternare Phosphoniumsalze im Laufe von 24 h nur ein bis zwei Molekullagen. Die Oberflachenbedeckung ist anfanglich nicht homogen. Die hier verwendete spezifische Kristallkeim-Methode von Karagounis bestatigt die analytischen Ergebnisse. Identification, by the “specific nucleus method according to Karagounis”, of the formation of secondary inhibitors Various onium…
Pulsed electric field (PEF) recovery of biomolecules from Chlorella: Extract efficiency, nutrient relative value, and algae morphology analysis
2023
This study investigated the effects of pulsed electric field (PEF) (3 kV/cm, 44 pulses, 99 kJ/kg), solvent (H2O or 50 % DMSO) and time (0, 10, 20, 30, 60, 90, 120 and 180 min) on the extraction of Chlorella antioxidant biomolecules and minerals. The results showed that PEF treatment increased the biomolecules recovery. For the extraction time of 120 min, more proteins and polyphenols were obtained using water, while more chlorophyll a and b, and carotenoids were obtained using 50 % DMSO as the extraction solvent. The extracts mineral concentration (PEF vs control) were analysed including Mg, P, Ca, Fe and Zn, and the Relative Nutrient Values results indicated that Chlorella H2O-extracts cou…
Syntheses, crystal structures, and oxidative DNA cleavage of some Cu(II) complexes of 5-amino-3-pyridin-2-yl-1,2,4-triazole
2004
Three new monomeric Cu(II) complexes of 5-amino-3-pyridin-2-yl-1,2,4-triazole (Hapt), [Cu(Hapt)(H(2)O)(2)(SO(4))] (1), [Cu(Hapt)(2)(H(2)O)(NO(3))](NO(3)) (2), and [Cu(Hapt)(2)(NCS-N)](NCS).H(2)O (3), have been prepared and characterized by single crystal X-ray diffraction. One distorted [CuN(2)O(2)+O(')] square-pyramidal (1), one distorted [CuN(3)O+N(')+O(')] octahedral (2), and one distorted [CuN(4)+N(')] intermediate between square-pyramidal and trigonal-bipyramidal (3) coordination configuration were found and are suggested to be due to the chelating nature of the ligand, which interacts with Cu(II) through the N4(triazole) and N(pyridine) atoms. Spectral properties of these chelates are…
CCDC 885911: Experimental Crystal Structure Determination
2013
Related Article: A.Suhonen, E.Nauha, K.Salorinne, K.Helttunen, M.Nissinen|2012|CrystEngComm|14|7398|doi:10.1039/c2ce25981h
CCDC 1555250: Experimental Crystal Structure Determination
2017
Related Article: Riia Annala, Aku Suhonen, Heikki Laakkonen, Perttu Permi, Maija Nissinen|2017|Chem.-Eur.J.|23|16671|doi:10.1002/chem.201703985
Thermodynamics of competing oxidation reactions of allyl methyl disulfide by hydrogen peroxide: a first principle molecular computational study on th…
2008
Allyl methyl disulfide, a peroxide scavenger, was studied together with three isomeric (two sulfoxides and one epoxide) forms of its mono-oxidized products. After a full conformational study of the reactant and three isomeric oxidized forms, the geometries were optimized at B3LYP/6-31G (d) level of theory. The epoxide form turned and to be more stable than either one of the two isomeric sulfoxides. Changes for Thermodynamic functions of oxidation reactions were calculated and from the δGreaction values the equilibrium constant for the interconversions of the oxidized products were estimated. Bader-type AIM analyses were performed on the electron density, computed at the B3LYP/6-311++G (d,p)…
Low-pressure pyrolysis of tBu2SO: synthesis and IR spectroscopic detection of HSOH.
2005
Sulfenic acid (HSOH, 1) has been synthesized in the gas-phase by low-pressure high-temperature (1150 degrees C) pyrolysis of di-tert-butyl sulfoxide (tBu(2)SO, 2) and characterized by means of matrix isolation and gas-phase IR spectroscopy. High-level coupled-cluster (CC) calculations (CCSD(T)/cc-pVTZ and CCSD(T)/cc-pVQZ) support the first identification of the gas-phase IR spectrum of 1 and enable its spectral characterization. Five of the six vibrational fundamentals of matrix-isolated 1 have been assigned, and its rotational-resolved gas-phase IR spectrum provides additional information on the O-H and S-H stretching fundamentals. Investigations of the pyrolysis reaction by mass spectrome…
The Interplay of Inverted Redox Potentials and Aromaticity in the Oxidized States of New π-Electron Donors: 9-(1,3-Dithiol-2-ylidene)fluorene and 9-(…
2006
Derivatives of 9-(1,3-dithiol-2-ylidene)fluorene (9) and 9-(1,3-dithiol-2-ylidene)thioxanthene (10) have been synthesised using Horner-Wadsworth-Emmons reactions of (1,3-dithiol-2-yl)phosphonate reagents with fluorenone and thioxanthen-9-one. X-ray crystallography, solution electrochemistry, optical spectroscopy, spectroelectrochemistry and simultaneous electrochemistry and electron paramagnetic resonance (SEEPR), combined with theoretical calculations performed at the B3P86/6-31G** level, elucidate the interplay of the electronic and structural properties in these molecules. These compounds are strong two-electron donors, and the oxidation potentials depend on the electronic structure of t…
Efficient synthesis of racemic and chiral alkenyl sulfoxides by palladium-catalyzed Suzuki coupling
2010
Alkenyl sulfoxide derivatives are obtained in high yields through a palladium-catalyzed Suzuki/Miyaura cross-coupling reaction of racemic and chiral 1-halo sulfoxides with aryl and alkenyl boronic acids. Chiral substrates react with no loss of optical purity and high optical yields. The reaction takes place with different palladium catalysts, such as Pd(PPh 3 ) 4 or Pd(OAc) 2 /DABCO. Although nitrogen ligands like DABCO lead to an active palladium catalyst, they are less effective than the phosphine ones.
Magneli-type tungsten oxide nanorods as catalysts for the selective oxidation of organic sulfides
2021
Selective oxidation of thioethers is an important reaction to obtain sulfoxides as synthetic intermediates for applications in the chemical industry, medicinal chemistry and biology or the destruction of warfare agents. The reduced Magneli-type tungsten oxide WO3−x possesses a unique oxidase-like activity which facilitates the oxidation of thioethers to the corresponding sulfoxides. More than 90% of the model system methylphenylsulfide could be converted to the sulfoxide with a selectivity of 98% at room temperature within 30 minutes, whereas oxidation to the corresponding sulfone was on a time scale of days. The concentration of the catalyst had a significant impact on the reaction rate. R…