2001 indole derivatives, isoindole derivatives

indole derivatives, isoindole derivativesR 0140

23 - 098A Facile Synthesis of 3H-Indolium Perchlorates by One-Pot Hy-drazone Formation/Fischer Indolization. — Twenty-eight indoliumsalts like (III) and (VI) are prepared by reaction of phenylhydrazines (I) and(IV), α-branched ketones (II) and (V), and perchloric acid via in situ formedhydrazones. This one-pot synthesis is of high practical significance because itworks without high pressure or sonochemical activation. Moreover, the productsprecipitate as crystals and hence the compounds are well separable solids whichcontain practically no impurities. The scope and limitations of this facilemethod are discussed. — (ZIMMERMANN, THOMAS; J. Heterocycl. Chem.37 (2000) 6, 1571-1574; Inst. Org. Chem., Univ. Leipzig, D-04103 Leipzig,Germany; EN)

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