The first observation of 1H-NMR spectrum of pentacene

Despite much interest in pentacene as a promising organic semiconductors, its chemical properties have scarcely been elucidated. Even such a fundamental data as H-1-NMR spectrum has not been reported yet due to poor solubility of pentacene in various solvents. Here we report the first observation of H-1 NMR spectrum of pentacene by using dimethyl sulfoxide-d(6) as solvent and heating the sample to 80degreesC. Not only the signal assignment but also the easily oxidizable property of pentacene was verified from the comparison between the spectra measured in degassed and non-degassed solvents.