1,3-Bis(5-bromothiophen-2-yl)-5,7-bis(2-ethylhexyl)benzo[1,2-c:4,5-c']dithiophene-4,8-dione, or BDD, CAS number 1415929-78-0, is an electron deficient building block which can be used for the synthesis of low band-gap polymer semiconductors such as PBDB-T (PCE12). With two side-branched side chains, the structure is more soluble and more easily processable for device fabrications.
BDD has been used to great success in our own lab for the synthesis of the high-performance OPV polymer semiconductor, PCE12 (PBDB-T).