title: Conjugated Ladder Polymers by a Cyclopentannulation Polymerization.
abstract: We report a nontraditional synthesis of cyclopentafused-polycyclic aromatic hydrocarbon embedded ladder polymers using a palladium catalyzed cyclopentannulation polymerization followed by a cyclodehydrogenation reaction. Donor-acceptor type polymers containing a cyclopenta[hi]aceanthrylene acceptor groups can be synthesized by a palladium catalyzed copolymerization between 9,10-dibromoanthracene and a variety of bis(arylethynyl)arenes to give polymers with molecular weights (Mn) of 9-22 kDa. The bis(arylethynyl)arenes were composed of benzene, thiophene, or thieno[3,2-b]thiophene moieties, which provided access to a series of four donor-acceptor copolymers. The polymers were subjected to cyclodehydrogenation with FeCl3to access rigid ladder type polymers with the conversion investigated by13C NMR of isotopically labeled polymers. The ladder polymers possess broad UV-Vis absorptions and narrow optical band gaps of 1.17-1.29 eV and are p-type semiconductors in organic field effect transistors.
authors.affiliation: Department of Chemistry and Biochemistry and the Materials Technology Center, Southern Illinois University , Carbondale, Illinois 62901, United States.
authors.forename: Sambasiva R
authors.initials: SR
authors.lastname: Bheemireddy
authors.affiliation: Department of Chemistry and Biochemistry and the Materials Technology Center, Southern Illinois University , Carbondale, Illinois 62901, United States.
authors.forename: Matthew P
authors.initials: MP
authors.lastname: Hautzinger
authors.affiliation: X-ray Science Division, Argonne National Laboratory , 9700 South Cass Ave., Argonne, Illinois 60439, United States.
authors.forename: Tao
authors.initials: T
authors.lastname: Li
authors.affiliation: X-ray Science Division, Argonne National Laboratory , 9700 South Cass Ave., Argonne, Illinois 60439, United States.
authors.forename: Byeongdu
authors.identifier: 0000-0003-2514-8805
authors.initials: B
authors.lastname: Lee
authors.affiliation: Department of Chemistry and Biochemistry and the Materials Technology Center, Southern Illinois University , Carbondale, Illinois 62901, United States.
authors.forename: Kyle N
authors.identifier: 0000-0002-5691-7876
authors.initials: KN
authors.lastname: Plunkett