title: One-pot synthesis and AFM imaging of a triangular aramide macrocycle.
abstract: Macrocyclizations in exceptionally good yields were observed during the self-condensation of N-benzylated phenyl p-aminobenzoates in the presence of LiHMDS to yield three-membered cyclic aramides that adopt a triangular shape. An ortho-alkyloxy side chain on the N-benzyl protecting group is necessary for the macrocyclization to occur. Linear polymers are formed exclusively in the absence of this Li-chelating group. A model that explains the lack of formation of other cyclic congeners and the demand for an N-(o-alkoxybenzyl) protecting group is provided on the basis of DFT calculations. High-resolution AFM imaging of the prepared molecular triangles on a calcite(10.4) surface shows individual molecules arranged in groups of four due to strong surface templating effects and hydrogen bonding between the molecular triangles.
authors.affiliation: Department of Chemistry, University of Fribourg , Chemin du Musée 9, CH-1700 Fribourg, Switzerland.
authors.forename: Christof
authors.initials: C
authors.lastname: Storz
authors.forename: Michael
authors.initials: M
authors.lastname: Badoux
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Hauke
authors.forename: Tomáš
authors.initials: T
authors.lastname: Šolomek
authors.forename: Angelika
authors.initials: A
authors.lastname: Kühnle
authors.forename: Thomas
authors.initials: T
authors.lastname: Bally
authors.forename: Andreas F M
authors.initials: AF
authors.lastname: Kilbinger
mesh_terms: D001549:Benzamides / Q000138:chemical synthesis* / Q000737:chemistry; D001952:Bridged-Ring Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D002119:Calcium Carbonate / Q000737:chemistry; D020650:Combinatorial Chemistry Techniques; D003500:Cyclization; D019281:Dimerization; D006860:Hydrogen Bonding; D047028:Macrocyclic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D018625:Microscopy, Atomic Force; D008958:Models, Molecular; D013499:Surface Properties
chemical_list: D001549:Benzamides; D001952:Bridged-Ring Compounds; D047028:Macrocyclic Compounds; D002119:Calcium Carbonate