title: Ultrathin Monomolecular Films and Robust Assemblies Based on Cyclic Catechols.
abstract: We introduce a newly designed catechol-based compound and its application for the preparation of homogeneous monomolecular layers as well as for robust assemblies on various substrates. The precisely defined cyclic catechol material (CyCat) was prepared from ortho-dimethoxybenzene in a phenolic resin-like synthesis and subsequent deprotection, featuring molecules with up to 32 catechol units. The CyCat's chemical structure was carefully assessed via matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF), proton nuclear magnetic resonance (1H NMR), diffusion ordered spectroscopy (2D DOSY) and high resolution electrospray ionization mass spectrometry (ESI MS) experiments. The formation of colloidal aggregates of the CyCat material in alkaline solution was followed by dynamic light scattering (DLS) and further verified by dropcasting CyCat from solution on highly oriented pyrolytic graphite (HOPG), which was examined by Kelvin probe force microscopy (KPFM). The adsorption behavior of the CyCat to form monomolecular layers was investigated in real time by surface plasmon resonance (SPR). Formation of these thin CyCat layers (1.6-2.1 nm) on Au, SiO2and TiO2substrates was corroborated by spectroscopic ellipsometry (SE) and X-ray photoelectron spectroscopy (XPS). The prepared coating perfectly reflects the surface structure of the underlying substrate and does not exhibit CyCat colloidal aggregates as verified by atomic force microscopy (AFM). The functional nature of the prepared catechol monolayers was evidenced by reaction with 4-bromophenethylamine and bis(3-aminopropyl)-terminated poly(ethylene oxide) (PEO). Multilayer assemblies were prepared by a simple procedure of iterative immersion in solutions of CyCat and a multifunctional amine on Au, SiO2and TiO2substrates forming thicker coatings (up to 12 nm). Postmodification with small organic molecules was performed to covalently attach trifluoroacetyl, tetrazole and 2-bromo-2-methylpropanoyl moieties to the amine groups of the multilayer assembly coating. Furthermore, the versatility of the novel multilayer coating was underpinned by "grafting-to" of phenacyl sulfide-terminated PEO and "grafting-from" of poly(methyl methacrylate) via surface-initiated atom transfer radical polymerization (ATRP).
authors.affiliation: Preparative Macromolecular Chemistry, Institut für Technische Chemie und Polymerchemie, Karlsruhe Institute of Technology (KIT) , Engesserstraße 18, 76128 Karlsruhe, Germany.|Institut für Biologische Grenzflächen, Karlsruhe Institute of Technology (KIT), Hermann-von-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany.
authors.forename: Markus M
authors.initials: MM
authors.lastname: Zieger
authors.affiliation: Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic v.v.i. , Heyrovsky sq. 2, 162 06 Prague, Czech Republic.
authors.forename: Ognen
authors.initials: O
authors.lastname: Pop-Georgievski
authors.affiliation: Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic v.v.i. , Heyrovsky sq. 2, 162 06 Prague, Czech Republic.
authors.forename: Andres
authors.initials: A
authors.lastname: de Los Santos Pereira
authors.affiliation: International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS) , 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan.
authors.forename: Elisseos
authors.initials: E
authors.lastname: Verveniotis
authors.affiliation: Preparative Macromolecular Chemistry, Institut für Technische Chemie und Polymerchemie, Karlsruhe Institute of Technology (KIT) , Engesserstraße 18, 76128 Karlsruhe, Germany.|Institut für Biologische Grenzflächen, Karlsruhe Institute of Technology (KIT), Hermann-von-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany.
authors.forename: Corinna M
authors.initials: CM
authors.lastname: Preuss
authors.affiliation: BASF SE, Registered Office , Ludwigshafen, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Zorn
authors.affiliation: BASF SE, Registered Office , Ludwigshafen, Germany.
authors.forename: Bernd
authors.initials: B
authors.lastname: Reck
authors.affiliation: Preparative Macromolecular Chemistry, Institut für Technische Chemie und Polymerchemie, Karlsruhe Institute of Technology (KIT) , Engesserstraße 18, 76128 Karlsruhe, Germany.|Institut für Biologische Grenzflächen, Karlsruhe Institute of Technology (KIT), Hermann-von-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany.|School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology (QUT) , 2 George Street, Brisbane, Queensland 4000, Australia.
authors.forename: Anja S
authors.initials: AS
authors.lastname: Goldmann
authors.affiliation: Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic v.v.i. , Heyrovsky sq. 2, 162 06 Prague, Czech Republic.|DWI - Leibniz-Institute for Interactive Materials and Institute of Technical and Macromolecular Chemistry, RWTH Aachen University , Forckenbeckstraße 50, 52074 Aachen, Germany.
authors.forename: Cesar
authors.initials: C
authors.lastname: Rodriguez-Emmenegger
authors.affiliation: Preparative Macromolecular Chemistry, Institut für Technische Chemie und Polymerchemie, Karlsruhe Institute of Technology (KIT) , Engesserstraße 18, 76128 Karlsruhe, Germany.|Institut für Biologische Grenzflächen, Karlsruhe Institute of Technology (KIT), Hermann-von-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany.|School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology (QUT) , 2 George Street, Brisbane, Queensland 4000, Australia.
authors.forename: Christopher
authors.identifier: 0000-0002-6745-0570
authors.initials: C
authors.lastname: Barner-Kowollik