%0 Journal Article %A Toriyama, Masaharu %A Maher, Tiffany R. %A Holovics, Thomas C. %A Vanka, Kumar %A Day, Victor W. %A Berrie, Cindy L. %A Thompson, Ward H. %A Barybin, Mikhail V. %D 2008 %T Multipoint Anchoring of the [2.2.2.2]Metacyclophane Motif to a Gold Surface via Self-Assembly: Coordination Chemistry of a Cyclic Tetraisocyanide Revisited %U https://acs.figshare.com/articles/journal_contribution/Multipoint_Anchoring_of_the_2_2_2_2_Metacyclophane_Motif_to_a_Gold_Surface_via_Self_Assembly_Coordination_Chemistry_of_a_Cyclic_Tetraisocyanide_Revisited/2943667 %R 10.1021/ic702401b.s002 %2 https://acs.figshare.com/ndownloader/files/4642438 %K coordination %K cm %K solution %K monolayer %K metacyclophane 3 %K η 4 species %K conformation %K interaction %K FTIR %K NC %K DFT %K Cyclic Tetraisocyanide Revisited %K surface %K film %X A one-pot transformation of bis(2-isocyano-3-methylphenyl)ethane affords gram quantities of 8,16,24,32-tetraisocyano[2.2.2.2]metacyclophane (3). The solid state structure of 3 is remarkably close to the lowest energy conformation found on the potential energy landscape for 3 by DFT. In solution, the structure of metacyclophane 3 is mobile but can be locked in a rectangular gaucheantigaucheanti conformation by coordination of the isocyanide substituents to the [W(CO)5] units to give [M]441111-3) (5). The tetranuclear [M]441111-3) motif featured in crystallographically characterized 5 may be present in several insoluble complexes of 3 previously described as mononuclear η4 species. A self-assembled monolayer of metacyclophane 3 is formed upon exposing a solution of 3 to the gold(111) surface with no precautions to exclude air or light. The monolayer nature of the film was confirmed by optical ellipsometry. The isocyanide stretching band for 3 shifts from 2119 cm−1 in solution to 2175 cm−1 upon chemisorption to metallic gold. The FTIR spectrum of the film indicates interaction of 3 with the gold surface via all four of its isocyanide anchors. No gold-facilitated oxidation of the −NC junctions was detected under ambient conditions. The energy cost associated with accessing the conformations of 3 suitable for μ41111 interaction of the molecule with the Au(111) surface is under 8 kcal/mol, a value that can be easily offset by formation of a gold−isocyanide bond. Two different μ41111 coordination arrangements of 3 with respect to gold atoms on the (111) face of the fcc Au lattice are suggested. %I ACS Publications