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The Cations and Anions of Cyclobutanetetraone Poly(Phenylhydrazones)



H S. El Khadem, M A. Shalaby, B Coxon


Six cyclobutanetetraone poly (arylhydrazones) have been treated with acids and bases, and the structures of the resulting anions and cations studied by UV/visible absorption and NMR spectroscopy. In acid media, all the hydrazones studied formed cations, which exhibited bathochromic shifts due to the extension of their resonance systems. However, in bases, only some (those which could enolize) formed anions that exhibited bypsochromic shifts; the others were unaltered.
Carbohydrate Research
No. 1


anions, bathochromic, cations, cyclobutanetetraone poly (phenylhydrazon, enolization, hypsochromic shift, NMR spectroscopy, ultraviolet/visible spectrophotometry


El, H. , Shalaby, M. and Coxon, B. (2002), The Cations and Anions of Cyclobutanetetraone Poly(Phenylhydrazones), Carbohydrate Research (Accessed April 20, 2024)
Created August 1, 2002, Updated February 19, 2017