Synthesis and properties of a new TSeF derivative containing a pyrazino-ring

A novel pyrazino-fused TSeF donor molecule 1 was synthesized. The donor 1 showed two pairs of reversible redox waves (+0.85 and +1.18 V vs. Ag/AgCl in PhCN). Many cation radical salts containing tetrahedral or octahedral anions showed metallic conducting behavior down to low temperature. Among them, the BF 4 - and ClO 4 - salts have unique donor arrangements, similar to the β-like structure and 2:1 donor-to-anion composition. These salts are two-dimensional conductors with a strong intermolecular interaction along the side-by-side direction of the donor molecule.