A new method of using supercritical carbon dioxide as a green solvent for synthesis and purification of 5,5′′′-bis(tridecafluorohexyl)-2,2′:5′,2:5,2′′′-quaterthiophene, which is one of n-type organic semiconducting materials

We have investigated synthesis as well as purification of 5,5'''-bis(tridecafluorohexyl)-2,2':5',2 '':5 '',2''' quaterthiophene (BFH-4 T, n -type organic semiconducting material) using supercritical carbon dioxide (scCO(2)) as a green solvent. BFH-4T was obtained in good selectivity and high yield by TDAE/PdC12-catalyzed reductive coupling reaction of 5-bromo-5'-(tridecafluorohexyl)-2,2'-bithiophene in scCO(2). We have also successfully established purification of the reaction mixture by passing scCO(2) in the reaction vessel. The product was yellow powder of BFH-4T with purity of more than 99% and Pd catalyst was not contained. (C) 2017 Elsevier Ltd. All rights reserved.