Synthesis, electronic structure, and complex formation of simple 1,1,4,4-tetrathiabutadienes

A new 1,1,4,4-tetrathiabutadiene donor, whose electronic structure is described by u.v.-photoelectron spectroscopy and molecular-orbital calculations, interacts with tetracyanotetrafluoroquinodimethane (TCNQF4) in CH2Cl2 to give weak complexes and in MeCN by electron transfer to provide the first example of solvent-dependent electron-transfer with the strong π-acceptor TCNQF4.