An exploration of the tolerance of a Pd-catalyzed direct arylation polycondensation under aerobic conditions was carried out. The polycondensation of 5-(2-ethylhexyl)thieno-[3,4-c]-pyrrole-4,6dione with 2,7-dibromo-9,9-dioctylfluorene was accomplished smoothly in air by refluxing the solvents, without the need for additional catalysts or additives. This simple modification allowed the use of commercially available reagent-grade solvents without further purification and produced the corresponding π-conjugated polymer with a molecular weight and yield comparable to those obtained under conventional oxygen-and moisture-free conditions. The facile synthetic protocol was applicable to the synthesis of other thienopyrroledione-based π-conjugated polymers. The obtained polymers served as semiconducting materials in organic light-emitting diodes (OLEDs) and organic photovoltaics. The effects of the terminal structure of the polymer on its photoluminescence and OLED device characteristics were also evaluated.

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Direct arylation polycondensation of 3,7-bis(4-bromophenyl)-1,5-bis(2-octyldodecyl)benzo[1,2-b:4,5-b']dipyrrole-2,6(1H,5H)-dione with 5-(2-ethylhexyl)-thieno-[3,4-c]-pyrrole-4,6-dione gave the corresponding benzodipyrrolidone-based conjugated polymer with a molecular weight of 147,000 in 92% yield. The optical and thermal properties of the polymer were evaluated. The polymer showed n-type semiconducting behavior in organic field-effect transistors with an electron mobility of 1.3 ± 0.2 x 10-3 cm 2 V-1 s-1 .