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Indolizine Derivatives (indolizine + derivative)
Selected AbstractsChemInform Abstract: One-Pot Synthesis of Indolizine Derivative and Its Application as Multidentate Ligand.CHEMINFORM, Issue 25 2008Osamu Niyomura Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 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] A Novel Coupling 1,3-Dipolar Cycloaddition Sequence as a Three-Component Approach to Highly Fluorescent IndolizinesHELVETICA CHIMICA ACTA, Issue 7 2005Alexandru Indolizines 4 and biindolizines 6 can be synthesized in moderate yields in a consecutive one-pot three-component process by a coupling/1,3-dipolar cycloaddition sequence of a (hetero)arenecarbonyl chloride 1, a terminal alkyne 2, and a suitable 1-(2-oxoethyl) pyridinium bromide 3 or 5, respectively (Schemes,1 and 2). After the Sonogashira coupling, a [2+3] cycloaddition of the in situ formed pyridinium ylide, an allyl-type 1,3-dipole, furnishes a cycloadduct that is instantaneously oxidatively aromatized to give the highly fluorescent indolizine derivatives that were unambiguously characterized by an X-ray-structure analysis of compound 4d (Fig.,1). Additionally, fluorescence studies with pyridinyl-substituted representatives reveal not only that indolizines and biindolizines are highly interesting fluorescence dyes but that their fluorescence color can also be reversibly switched upon altering the pH of the medium. [source] Indolizines, triazolo[4,3- a]pyridines, benzimidazo[1,2- d]oxadiazoles, and pyrazolo[1,5- c]triazoles via nitrogen and sulfur ylidesHETEROATOM CHEMISTRY, Issue 6 2004Kamal M. Dawood The pyridinium salts 2a,b reacted with dimethyl acetylenedicarboxylate (DMAD) to give the indolizine derivatives 6a,b. Pyridinium salts 2a,b also reacted with pyrazole-5-diazonium salt to afford the hydrazonoyl bromides 8a,b, which on treatment with aqueous ethanolic sodium carbonate furnished the 8aH -1,2,4-triazolo[4,3- a]pyridine 10. When sulfonium bromide 11 was treated with nitrous acid and with pyrazole-5-diazonium salt, it afforded the new hydroximoyl and hydrazonoyl halides 12 and 17, respectively. Compound 12 reacted with 2-methylthiobenzimidazole to furnish benzimidazo[1,2- d]-1,2,4-oxadiazole derivative 14. Treatment of either 12 with 3-phenyl-5-aminopyrazole or 17 with triethylamine resulted in the formation of the same product: pyrazolo[1,5- c]-1,2,4-triazole derivative 16. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:432,436, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20037 [source] Synthesis of a library of 1,2,3,7-tetrasubstituted indolizines using poly(ethylene glycol) as soluble supportJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 3 2006Guizhou Yue A library of 1,2,3,7-tetrasubstituted indolizines has been synthesized using poly(ethylene glycol) (PEG) as soluble polymer support. The PEG-bound pyridinium salts reacted with alkenes or alkynes in the presence of Et3N via 1,3-dipolar cycloaddition to give PEG-bound indolizine derivatives, which were cleaved by 1 % KCN/MeOH to afford 1,2,3,7-tetrasubstituted indolizines in good to excellent yields. [source] | ||||||||||