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DOI: 10.1039/A804505D (Paper) Reference Section for: J. Chem. Soc., Perkin Trans. 2, 1998, 2239-2242

Tris(1-naphthyl)- and tris(2-naphthyl)methyl cations: highly crowded triarylmethyl cations[hair space]1

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George A. Olah, Qimu Liao, J. Casanova, Robert Bau, Golam Rasul and G. K. Surya Prakash

Abstract

The highly hindered tris(1-naphthyl)methyl and tris(2-naphthyl)methyl cations 3 and 5 have been prepared under long lived stable ion conditions and characterized by 13C NMR spectroscopy at low temperatures. The latter can abstract hydride from cycloheptatriene to afford tris(2-naphthyl)methane 7, but the reaction of cycloheptatriene with the more crowded cation 3 failed to give the corresponding hydrocarbon. A primary kinetic isotope effect, kH/kD = 7.1 ± 0.5, found in the former case supports a colinear hydride abstraction mechanism. The ions 3 and 5 upon quenching rearranged to give a mixture of isomeric 13-(1-naphthyl)-1,2,7,8-dibenzofluorene 4 and 13-(2-naphthyl)-2,3,6,7-dibenzofluorene 6, respectively.

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