Activation of Electrophilicity of Stable Y-Delocalized Carbamate Cations in Intramolecular Aromatic Substitution Reaction: Evidence for Formation of Diprotonated …

…, K Kawamoto, H Sugimoto, S Nakamura…

Index: Kurouchi, Hiroaki; Kawamoto, Kyoko; Sugimoto, Hiromichi; Nakamura, Satoshi; Otani, Yuko; Ohwada, Tomohiko Journal of Organic Chemistry, 2012 , vol. 77, # 20 p. 9313 - 9328,16

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Citation Number: 10

Abstract

Although cations with three heteroatoms, such as monoprotonated guanidine and urea, are stabilized by Y-shaped conjugation and such Y-conjugated cations are sufficiently basic to be further protonated (or protosolvated) to dications in strongly acid media, only O- monoprotonated species have been detected in the case of carbamates even in magic acid. We found that the trifluoromethanesulfonic acid-catalyzed cyclization of ...