Donor–acceptor complex of a new bis‐TTF donor containing a pyridine diester spacer with TCNQ as the acceptor: a disappointing system

A new bis‐TTF donor (TTF is tetrathiafulvalene) containing a pyridine diester spacer, namely bis{2‐(6,7‐tetramethylene‐3‐methylsulfanyltetrathiafulvalen‐2‐yl)sulfanyl]ethyl} pyridine‐2,6‐dicarboxylate–tetracyanoquinodimethane–dichloromethane (2/1/2), 2C₃₃H₃₃NO₄S₁₂·C₁₂H₄N₄·2CH₂Cl₂, has been synthesized and its electron‐donating ability determined by cyclic voltammetry. The electrical conductivity and crystal structure of this donor–acceptor (DA) complex with TCNQ (tetracyanoquinodimethane) as the acceptor are presented. The TCNQ moiety lies across a crystallographic inversion centre. In the crystal structure, TTF and TCNQ entities are arranged in alternate stacks; this feature, together with the bond lengths of the TCNQ molecule, suggest that the expected charge transfer has not occurred and that the D and A entities are in the neutral state, in agreement with the poor conductivity of the material (σ_RT = 2 × 10^?6 S cm^?1).