This research quantifies the gas release rate from a natural shallow methane seep site in the Laspi Bay (Black Sea), whose origin is thermocatalytic. An adaptive single bubble identification technique was applied to analyze gas volume and release rates from passive acoustic data. Gas from the seafloor was emitted by single bubbles that occurred in clusters.
View Article and Find Full Text PDFIn this study, the electrochemical coupling of nitrosoarenes with ammonium dinitramide is discovered, leading to the facile construction of the nitro--azoxy group, which represents an important motif in the design of energetic materials. Compared to known approaches to nitro--azoxy compounds involving two chemical steps (formation of azoxy group containing a leaving group and its nitration) and demanding expensive, corrosive, and hygroscopic nitronium salts, the presented electrochemical method consists of a single step and is based solely on nitrosoarenes and ammonium dinitramide. The dinitramide salt plays the roles of both the electrolyte and reactant for the coupling.
View Article and Find Full Text PDFRadical ring-opening oxyimidation of cyclobutanols and cyclopropanols with the formation of ω-functionalized ketones was discovered. The oxidative C-O coupling proceeds the interception of a primary alkyl radical generated from a cyclic alcohol with a reactive radical generated , which is an electron-deficient -oxyl radical. The developed conditions allow for the balanced generation rates of carbon- and -oxyl radicals, which are necessary for their selective cross-recombination.
View Article and Find Full Text PDFSelective oxidative C-O coupling of hydrazones with diacetyliminoxyl is demonstrated, in which diacetyliminoxyl plays a dual role. It is an oxidant (hydrogen atom acceptor) and an O-partner for the oxidative coupling. The reaction is completed within 15-30 min at room temperature, is compatible with a broad scope of hydrazones, provides high yields in most cases, and requires no additives, which makes it robust and practical.
View Article and Find Full Text PDFThe intermolecular oxime radical addition to CC bonds was observed and studied for the first time. The diacetyliminoxyl radical was proposed as a model radical reagent for the study of oxime radical reactivity towards unsaturated substrates, which is important in the light of the active development of synthetic applications of oxime radicals. In the present work it was found that the diacetyliminoxyl radical reacts with vinylarenes and conjugated dienes to give radical addition products, whereas unconjugated alkenes can undergo radical addition or allylic hydrogen substitution by diacetyliminoxyl depending on the substrate structure.
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