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Your search keyword '"B. A. Stark"' showing total 4 results
Start Over Author "B. A. Stark" Journal chemical communications
4 results on '"B. A. Stark"'

1. Photoassisted oxidation of ruthenium(<scp>ii</scp>)-photocatalysts Ru(bpy)32+ and Ru(bpz)32+ to RuO4: orthogonal tandem photoredox and oxidation catalysis

Author

Dirk Alpers, Christian B. W. Stark, Malte Brasholz, and Malte Gallhof

Subjects
Tandem, 010405 organic chemistry, Chemistry, Visible light irradiation, Metals and Alloys, chemistry.chemical_element, Nanotechnology, General Chemistry, 010402 general chemistry, Photochemistry, 01 natural sciences, Catalysis, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Ruthenium, Radical ion, Materials Chemistry, Ceramics and Composites
Abstract

Common photoredox catalysts Ru(bpy)3(2+) and Ru(bpz)3(2+) are rapidly converted into Ruthenium(viii)-oxide through continuous visible light irradiation in the presence of NaIO4 or H5IO6. This hitherto unreported photoassisted catalyst oxidation was utilized in the development of tandem catalytic protocols which combine a photoredox reaction with a subsequent RuO4-mediated oxidation. The new concept was demonstrated through one-pot radical cation Diels-Alder (RCDA)/1,5-diene cyclisation sequences.

Published
2016
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2. A new catalytic oxidative cleavage reaction to furnish lactones

Author

Christian B. W. Stark and Stefanie Roth

Subjects
Molecular Structure, Metals and Alloys, Periodic acid, General Chemistry, Catalysis, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Lactones, chemistry.chemical_compound, chemistry, Alcohols, Materials Chemistry, Ceramics and Composites, Organic chemistry, Oxidative cleavage, Oxidation-Reduction
Abstract

A highly efficient oxidative cleavage reaction of THF and THP alcohols to gamma- and delta-lactones using catalytic PCC (1 mol%) and periodic acid as terminal oxidant is presented.

Published
2008
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3. The effect of ruthenium(iii) chloride on the formation of protonated parent ions in electrospray mass spectrometry

Author

Tatiana L. Fonseca, Paul J. Gates, Norberto Peporine Lopes, and Christian B. W. Stark

Subjects
Spectrometry, Mass, Electrospray Ionization, Collision-induced dissociation, Electrospray ionization, Inorganic chemistry, Analytical chemistry, Protonation, Catalysis, Sample preparation in mass spectrometry, Ion, chemistry.chemical_compound, Materials Chemistry, Monensin, Furans, Ruthenium(III) chloride, Ions, Cyclodextrins, Valinomycin, beta-Cyclodextrins, Metals and Alloys, General Chemistry, Fast atom bombardment, Alkali metal, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, chemistry, Ceramics and Composites, Ruthenium Compounds, Protons
Abstract

We report the use of RuCl3 as an "alkali metal sponge". This is a general and highly efficient method for generating protonated parent ions for a variety of compounds that usually do not show this ion in electrospray mass spectrometry. This technique is demonstrated to be highly useful in "cleaning up" spectra from multiply metallated ions, thereby substantially improving the signal-to-noise ratio.

Published
2003
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