title: Synthesis, optical, and electrochemical properties of a new family of dendritic oligothiophenes.
abstract: A new class of semi-flexible dendrimers with oligothiophene (OT) arms up to the third generation have been synthesized and investigated. The synthetic methods employed include a combination of palladium-catalyzed Stille cross-coupling reactions for oligothiophenes, Sonogashira cross-coupling reactions for building blocks, and carbodiimide-mediated esterification for building up the various dendrimers. The optical and electrochemical properties of this series of oligothiophenes-based dendrimers are shown to be strongly influenced by their morphologies as demonstrated by their pronounced solvatochromic and thermochromic responses under different environmental conditions. Introducing rigid oligothiophene arms to shape non-persistent ester-linked dendrimers causes higher generation dendrimers (G2 and G3) to exhibit solvatochromism and thermochromism, while their oligomeric counterpart (3b) and lower generation (G1) analogue do not. Spectroscopic changes due to both intramolecular and intermolecular aggregations are observed.
authors.affiliation: Department of Chemistry, University of Rochester, Rochester, New York 14627, USA.
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
authors.forename: Chunchang
authors.initials: C
authors.lastname: Zhao
authors.forename: Jinhua
authors.initials: J
authors.lastname: Yang
authors.forename: Mbiya
authors.initials: M
authors.lastname: Kapiamba
authors.forename: Olesya
authors.initials: O
authors.lastname: Haze
authors.forename: Lewis J
authors.initials: LJ
authors.lastname: Rothberg
authors.forename: Man-Kit
authors.initials: MK
authors.lastname: Ng
mesh_terms: D004563:Electrochemistry; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D013876:Thiophenes / Q000737:chemistry*
chemical_list: D013876:Thiophenes