From ar clustering dynamics to Ar solvation for Na+-benzene

M Albertí1, A Aguilar, J M Lucas

  • 1Departament de Química Física i Centre de Recerca en Química Teorica, Parc Científic, Universitat de Barcelona, Martí i Franquès, 1, 08028 Barcelona, Spain. m.alberti@ub.edu

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Simple unsubstituted benzene has six aromatic protons, all chemically equivalent. Therefore, benzene exhibits only a singlet peak at δ 7.3 ppm in the 1H NMR spectrum. The observed shift is far downfield because the aromatic ring current strongly deshields the protons. Any substitution on the benzene ring makes the aromatic protons nonequivalent, and the protons split each other. The peak is, therefore, no longer a singlet and the splitting pattern and their associated coupling constants depend...
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Treating arylamines with nitrous acid gives aryldiazonium salts that are effective substrates in nucleophilic aromatic substitution reactions. The diazonio group in these salts can be easily displaced by different nucleophiles, yielding a wide variety of substituted benzenes. The leaving group departs as nitrogen gas, and this easy elimination is the driving force for the substitution reaction.
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