SUBSTITUTED QUINODIMETHANS: VIII. SALTS DERIVED FROM THE 7,7,8,8-TETRACYANOQUINODIMETHAN ANION–RADICAL AND BENZOLOGUES OF QUATERNARY PYRAZINIUM CATIONS

Our continued study of derivatives of the 7,7,8,8-tetracyanoquinodimethan anion–radical (TCNQ−•) has shown that the simple N-methylphenazinium salt (IIa) exhibits a volume electrical resistivity of 7 × 10−3 Ω cm and thus is the most highly electrically conductive organic compound known. In contrast, the N-ethyl analogue has a resistivity of 109 Ω cm. Electrical properties of pyrazinium, quinoxalinium, and phenazinium analogues, including phenazine-derived cation–radical salts of TCNQ−•, are discussed. Qualitative observations are made concerning the electron paramagnetic resonance of the N,N′-dimethyldihydrophenazinylium cation–radical.