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Aryl Diazonium Salts (aryl + diazonium_salt)
Selected AbstractsChemInform Abstract: Hydroperoxides and Aryl Diazonium Salts as Reagents for the Functionalization of Non-Activated Olefins.CHEMINFORM, Issue 27 2010Olga Blank Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Benzofuranyl-pyran-2-ones, -pyridazines, and -pyridones from naturally occurring furochromones (visnagin and khellin)HETEROATOM CHEMISTRY, Issue 1 2004Eman M. Keshk The novel and versatile enaminones 2a,b were synthesized by treatment of visnaginone methyl ether 1a or khellinone methyl ether 1b with N,N -dimethylformamide dimethylacetal. They were reacted with hippuric acid or N -acetylglycine to yield benzofuran-5-yl-2H-pyran-2-ones 3a,d. The reaction of 2a,b with cyanoacetamide and malononitrile dimer in sodium ethoxide gave benzofuran-5-yl-pyridones 4a,b and [benzofuran-5-yl-1H-pyridine-2-ylidene] malononitrile 5a, respectively. Refluxing 2a,b with hydrazine hydrate or with hydroxyla- mine afforded benzofuran-5-yl-1H-pyrazoles 6a,b and benzofuran-5-yl-isoxazoles 7a,b, respectively. Moreover, 2a,b coupled with aryl diazonium salt in the presence of sodium hydroxide to yield 3-(benzofuran-5-yl)-2-aryl-hydrazono-3-oxo-propanals 8a,b which were excellent precursors for the synthesis of pyridazines 9,12. © 2003 Wiley Periodicals, Inc. 15:85,91, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10219 [source] A Scalable Route to Highly Functionalized Multi-Walled Carbon Nanotubes on a Large ScaleMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 8 2008Xianhong Chen Abstract A scalable and solvent-free chemical process to obtain highly functionalized and dispersible multi-walled carbon nanotubes is reported. Highly functionalized multi-walled carbon nanotubes have been prepared using in situ generated aryl diazonium salts in the presence of ammonium persulfate and 2,2,-azoisobutyronitrile by solvent-free techniques. In the Raman spectra of the resulting materials, characteristic peaks, the D- and G-bands, are shifted by about 10 cm,1 to lower frequencies. At the same time, the relative intensity ratios between the D- and G-bands increase in comparison to that in the spectrum of the purified product. Fourier-transform infrared spectroscopy reveals the presence of the functional groups on the surface. Transmission electron microscopy images directly confirm the significant build-up of sidewall organic moieties on the treated materials. The weight loss of various functional moieties determined by thermogravimetry,differential scanning calorimetry analysis is about 18,33%. The dispersibility of the functionalized materials in solvents, such as chloroform, tetrahydrofuran, and water, is obviously improved. [source] Chemical Derivatisation of Multiwalled Carbon Nanotubes Using Diazonium Salts,CHEMPHYSCHEM, Issue 11 2004Charles G. R. Heald A facile and versatile modification strategy: A chemically activated method of covalently derivatising carbon powder, via the chemical reduction of aryl diazonium salts with hypophosphorous acid, to include the covalent derivatisation of multiwalled carbon nanotubes (MWCNTs) is demonstrated. The specific molecular environments of 1-anthraquinonyl moieties attached to MWCNTs (see picture) produce interesting effects. [source] | ||||||||||