title: Trimeric and Tetrameric Electron-Deficient Porphyrin Tapes.
abstract: New hybrid porphyrin tapes comprising meso-3,5-di-tert-butylphenyl-substituted Zn(II) -porphyrins (D) and meso-pentafluorophenyl-substituted Zn(II) -porphyrins (A) were synthesized via cross-condensation of meso-formyl porphyrins 1, 5, and 9 with oligopyrromethanes 2 and 6 as key steps. These hybrid tapes exhibit improved solubilities and enhanced chemical stability as compared with original Dn porphyrin tapes, and all display remarkably coplanar structures favorable for π-conjugation. The absorption spectrum of ADDA displays Q-like bands at 1400 and 1657 nm with a vibronic structure characteristic of porphyrinoids. The cyclic voltammograms exhibited positively shifted oxidation and reduction waves in the order of DDD<DAD<ADA<AAA. Tetrameric tape ADDA displays five reversible waves in a narrow range of 1.13 V. Two-photon absorption (TPA) measurement confirmed that the π-conjugation path is extended from 12 to ADDA and the molecular polarizability of ADA is larger than that of AAA.
authors.affiliation: Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan.
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Mori
authors.affiliation: Department of Chemistry, Yonsei University, Seodaemoon-gu, Shinchon-dong 134, Seoul, 120-749, Republic of Korea.
authors.forename: Taeyeon
authors.initials: T
authors.lastname: Kim
authors.affiliation: Department of Chemistry, Yonsei University, Seodaemoon-gu, Shinchon-dong 134, Seoul, 120-749, Republic of Korea. dongho@yonsei.ac.kr.
authors.forename: Dongho
authors.initials: D
authors.lastname: Kim
authors.affiliation: Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan. osuka@kuchem.kyoto-u.ac.jp.
authors.forename: Atsuhiro
authors.initials: A
authors.lastname: Osuka
mesh_terms: D018360:Crystallography, X-Ray; D004583:Electrons; D008958:Models, Molecular; D015394:Molecular Structure; D011166:Porphyrins / Q000737:chemistry*
chemical_list: D011166:Porphyrins
keywords: aromaticity; conjugation; molecular wires; porphyrin tapes; porphyrinoids