Rearrangements of N??Heterocyclic Carbenes of Pyrazole to 4??Aminoquinolines and Benzoquinolines

…, N Muenster, TA Rokob, I Pápai…

Index: Dreger, Andrij; Cisneros Camuna, Rafael; Munster, Niels; Andras Rokob, Tibor; Papai, Imre; Schmidt, Andreas European Journal of Organic Chemistry, 2010 , # 22 p. 4296 - 4305

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Citation Number: 15

Abstract

Abstract 1-Phenyl-substituted pyrazolium salts, formed by quaternization of pyrazoles with benzyl halides or long-chain alkyl halides, deprotonate to pyrazol-3-ylidenes that undergo a sequence of ring-opening, ring-closure, and tautomerization to new substituted 4- aminoquinolines. Similarly, 1-naphthyl-substituted pyrazolium-3-carboxylates decarboxylate on heating in toluene to give benzoquinolines in excellent yields by an analogous ...