Novel selenium variants of BEDT-TTF

Bis(ethyleneselenothio)-tetrathiafulvalene (BEST-TTF) and -tetraselenafulva lene (BEST-TSF) have been synthesized using the following two consecutive c yclization methods: (1) one-pot construction of the inner 1,3-dichalcogenol e ring from THP-protected 2-(ethynylthio)ethanol and (2) intramolecular tra nsalkylation on a selenium atom toward the formation of the outer dihydroth iaselenin ring. The X-ray crystallographic analysis of BEST-TSF revealed th at its molecular and crystal structures are essentially similar to those of BEDT-TTF and related selenium variants.