title: Ultra stable self-assembled monolayers of N-heterocyclic carbenes on gold.
abstract: Since the first report of thiol-based self-assembled monolayers (SAMs) 30 years ago, these structures have been examined in a huge variety of applications. The oxidative and thermal instabilities of these systems are widely known, however, and are an impediment to their widespread commercial use. Here, we describe the generation of N-heterocyclic carbene (NHC)-based SAMs on gold that demonstrate considerably greater resistance to heat and chemical reagents than the thiol-based counterparts. This increased stability is related to the increased strength of the gold-carbon bond relative to that of a gold-sulfur bond, and to a different mode of bonding in the case of the carbene ligand. Once bound to gold, NHCs are not displaced by thiols or thioethers, and are stable to high temperatures, boiling water, organic solvents, pH extremes, electrochemical cycling above 0 V and 1% hydrogen peroxide. In particular, benzimidazole-derived carbenes provide films with the highest stabilities and evidence of short-range molecular ordering. Chemical derivatization can be employed to adjust the surface properties of NHC-based SAMs.
authors.affiliation: 1] Queen's University, Department of Chemistry, Chernoff Hall, Kingston, Ontario K7L 3N6, Canada [2] Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Chikusa, Nagoya 464-8602, Japan.
authors.forename: Cathleen M
authors.initials: CM
authors.lastname: Crudden
authors.affiliation: Queen's University, Department of Chemistry, Chernoff Hall, Kingston, Ontario K7L 3N6, Canada. jhh@queensu.ca
authors.forename: J Hugh
authors.initials: JH
authors.lastname: Horton
authors.affiliation: Queen's University, Department of Chemistry, Chernoff Hall, Kingston, Ontario K7L 3N6, Canada.
authors.forename: Iraklii I
authors.initials: II
authors.lastname: Ebralidze
authors.affiliation: Queen's University, Department of Chemistry, Chernoff Hall, Kingston, Ontario K7L 3N6, Canada.
authors.forename: Olena V
authors.initials: OV
authors.lastname: Zenkina
authors.affiliation: Queen's University, Department of Physics, Engineering Physics and Astronomy, Stirling Hall, Kingston, Ontario K7L 3N6, Canada.
authors.forename: Alastair B
authors.initials: AB
authors.lastname: McLean
authors.affiliation: Queen's University, Department of Physics, Engineering Physics and Astronomy, Stirling Hall, Kingston, Ontario K7L 3N6, Canada.
authors.forename: Benedict
authors.initials: B
authors.lastname: Drevniok
authors.affiliation: 1] Department of Physical and Environmental Sciences, University of Toronto Scarborough, Toronto, Ontario M1C 1A4, Canada [2] Department of Chemistry, University of Toronto, Toronto M5S 3H6, Canada.
authors.forename: Zhe
authors.initials: Z
authors.lastname: She
authors.affiliation: 1] Department of Physical and Environmental Sciences, University of Toronto Scarborough, Toronto, Ontario M1C 1A4, Canada [2] Department of Chemistry, University of Toronto, Toronto M5S 3H6, Canada.
authors.forename: Heinz-Bernhard
authors.initials: HB
authors.lastname: Kraatz
authors.affiliation: Queen's University, Department of Chemistry, Chernoff Hall, Kingston, Ontario K7L 3N6, Canada.
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: Mosey
authors.affiliation: Queen's University, Department of Chemistry, Chernoff Hall, Kingston, Ontario K7L 3N6, Canada.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Seki
authors.affiliation: Queen's University, Department of Chemistry, Chernoff Hall, Kingston, Ontario K7L 3N6, Canada.
authors.forename: Eric C
authors.initials: EC
authors.lastname: Keske
authors.affiliation: Queen's University, Department of Chemistry, Chernoff Hall, Kingston, Ontario K7L 3N6, Canada.
authors.forename: Joanna D
authors.initials: JD
authors.lastname: Leake
authors.affiliation: Queen's University, Department of Chemistry, Chernoff Hall, Kingston, Ontario K7L 3N6, Canada.
authors.forename: Alexander
authors.initials: A
authors.lastname: Rousina-Webb
authors.affiliation: Queen's University, Department of Chemistry, Chernoff Hall, Kingston, Ontario K7L 3N6, Canada.
authors.forename: Gang
authors.initials: G
authors.lastname: Wu
mesh_terms: D006046:Gold / Q000737:chemistry*; D006571:Heterocyclic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D008697:Methane / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry; D015394:Molecular Structure; D010316:Particle Size; D013499:Surface Properties
chemical_list: D006571:Heterocyclic Compounds; C030011:carbene; D006046:Gold; D008697:Methane
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