Isomerically pure 5,11-dibromo-ADT was used to create contorted aromatics with large splay angles, low band gaps, and low LUMOs.

Novel coumarinylmethyl photobase generators (PBGs) that induce polymerization upon exposure to visible light are described. PBG composition governs anionic vs. radical mechanisms, which will lead to disparate polymer topologies and properties.

A series of donor-acceptor copolymers with dicyclopenta[cd,jk]pyrene and dicyclopenta[cd,lm]perylene acceptor units was prepared via palladium catalyzed cyclopenta-annulation reactions. The acceptor units were paired with diethynyl containing donor groups based on benzo[1,2-b:4,5-b']dithiophene, thieno[3,2-b]thiophene, and 4-octyl-4H-dithieno[3,2-b:2 0 ,3 0-d]pyrrole to create six polymer variants. The cyclopentannulation polymerization resulted in copolymers with molecular weights (Mn) of 6-14 kDa and broad light absorption in the visible region with band gaps of 1.38-1.85 eV. The synthetic methodology, as well as optoelectronic properties, including thin-film absorption and cyclic voltammetry, of the donor-acceptor copolymers are presented.