Substituent-induced polarization of charge in phenalenyl anions

Abstract

The effect of trimethylsilyl, alkynyl and cyano substituents on the charge distribution of the phenalenyl anionic nucleus was examined using semiempirical calculations and NMR spectroscopy. With these techniques it was demonstrated that the trimethylsilyl and cyano substituents are capable of attracting adjacent negative charge. Examples of reactions from the literature confirm the charge-attracting capabilities of the trimethylsilyl substituent. The alkynyl substituent was shown to perturb the charge distribution of the phenalenyl moiety to a much lesser degree than the vinyl substituent in the 1-hydropyrenyl anion. Copyright © 1999 John Wiley & Sons, Ltd.