title: Surface-confined conformers and coassembly-induced conformer resolution.
abstract: Stereoisomerism is a fundamental chemistry issue and has been intensively investigated because of its importance in organic chemistry, biology, and pharmacology. Molecules with freely rotatable single bonds have many interconvertable conformers. Herein, we report the surface-adsorption-induced conformer resolution by employing azobenzene-3,3-dicarboxylic acid (ADA-33) as a model compound. Two linear assembly phases composed of trans conformers on a highly oriented pyrolytic graphite (HOPG) surface are observed by scanning tunneling microscopy. With the codeposition with 1-octanoic acid (OA), only one trans conformer of ADA-33 can be recognized by OA to form a two-component assembly with alternately arranged ADA-33 and OA stripes, which can be attributed to the epitaxial assembly of ADA-33 and OA on the HOPG surface, and weak hydrogen bonding exists between conformer I and OA molecules. The results are of significance with respect to the discrimination and resolution of conformers on a solid surface and provide molecular insights into the coadsorption assembly on the surface.
authors: Institute of Chemistry, Chinese Academy of Sciences, and Beijing National Laboratory for Molecular Sciences, Beijing 100190, China.
authors: Cui-Zhong
authors: CZ
authors: Guan
authors: Ting
authors: T
authors: Chen
authors: Jing-Yi
authors: JY
authors: Wu
authors: Qing
authors: Q
authors: Chen
authors: Dong
authors: D
authors: Wang
authors: Peter J
authors: PJ
authors: Stang
authors: Li-Jun
authors: LJ
authors: Wan
mesh_terms: D001391:Azo Compounds / Q000737:chemistry*; D002210:Caprylates / Q000737:chemistry; D006108:Graphite / Q000737:chemistry; D016252:Microscopy, Scanning Tunneling; D013237:Stereoisomerism
chemical_list: D001391:Azo Compounds; D002210:Caprylates; D006108:Graphite; C009850:azobenzene; C031492:octanoic acid