SYNTHESIS AND X-RAY CRYSTAL-STRUCTURE OF A SELENOPHENOQUINONOID-EXTENDED DONOR, BEDT-BDTS, AFFORDING HIGHLY CONDUCTING TETRACYANOQUINODIMETHANE AND I-3 COMPLEXES

ithio-1,3-dithiol-2-yliden)-2,5-dihydroselenophene (BEDT-BDTS), a sele nophenoquinonoid-extended analogue of bis(ethylenedithio) tetrathiaful valenes (BEDT-TTF), has been synthesized as a promising candidate for an electron-donating component of high T-c ,organic superconductors. B EDT-BDTS is air-stable and has a significantly enhanced electron-donat ing ability compared with that of BEDT-TTF. The molecular and crystal structures of BEDT-BDTS have been determined by single crystal X-ray a nalysis in which short intermolecular: S ... S contacts have been foun d in the side-by-side directions of the donor arrangements. A 1:1 TCNQ complex and a 3:1 I,(-)(3) radical cation salt of BEDT-BDTS have been obtained and proved to exhibit fairly high room temperature conductiv ities.