One-step synthesis of polycyclic thianthrenes from unfunctionalized aromatics by thia-APEX reactions

Abstract

In this paper, thia-APEX reactions affording π-extended thianthrene derivatives from unfunctionalized aromatics are described. By utilizing S-diimidated 1,2-arenedithiols as benzene-1,2-dithiol dication synthons, new benzodithiine arms were fused to the unfunctionalized aromatic substrates in one step, affording π-extended thianthrenes in 21–87% yields. The present thia-APEX reaction occurs with equimolar amounts of aromatic substrates and S-diimidated 1,2-arenedithiols and a catalytic amount of TfOH, which is advantageous for the efficient creation of novel π-extended thianthrenes. In addition, the unique solid state packing structures and photophysical properties of the synthesized π-extended thianthrenes were elucidated in this study.