title: A terminally protected dipeptide: from crystal structure and self-assembly, through co-assembly with carbon-based materials, to a ternary catalyst for reduction chemistry in water.
abstract: A terminally protected, hydrophobic dipeptide Boc-L-Cys(Me)-L-Leu-OMe (1) was synthesized and its 3D-structure was determined by single crystal X-ray diffraction analysis. This peptide is able to hierarchically self-assemble in a variety of superstructures, including hollow rods, ranging from the nano- to the macroscale, and organogels. In addition, 1 is able to drive fullerene (C60) or multiwalled carbon nanotubes (MWCNTs) in an organogel by co-assembling with them. A hybrid 1-C60–MWCNT organogel was prepared and converted (through a high vacuum-drying process) into a robust, high-volume, water insoluble, solid material where C60 is well dispersed over the entire superstructure. This ternary material was successfully tested as a catalyst for: (i) the reduction reaction of water-soluble azo compounds mediated by NaBH4 and UV-light with an overall performance remarkably better than that provided by C60 alone, and (ii) the NaBH4-mediated reduction of benzoic acid to benzyl alcohol. Our results suggest that the self-assembly properties of 1 might be related to the occurrence in its single crystal structure of a sixfold screw axis, a feature shared by most of the linear peptides known so far to give rise to nanotubes.
authors.affiliation: Department of Chemical Sciences, University of Padova, 35131 Padova, Italy. alessandro.moretto.1@unipd.it.
authors.forename: Daniela
authors.initials: D
authors.lastname: Mazzier
authors.affiliation: Department of Chemical Sciences, University of Padova, 35131 Padova, Italy. alessandro.moretto.1@unipd.it.
authors.forename: Francesco
authors.initials: F
authors.lastname: Carraro
authors.affiliation: Institute of Biomolecular Chemistry, Padova Unit, CNR, 35131 Padova, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Crisma
authors.affiliation: Institute for Energetics and Interphases, CNR, 35131 Padova, Italy.
authors.forename: Marzio
authors.initials: M
authors.lastname: Rancan
authors.affiliation: Department of Chemical Sciences, University of Padova, 35131 Padova, Italy. alessandro.moretto.1@unipd.it and Institute of Biomolecular Chemistry, Padova Unit, CNR, 35131 Padova, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Toniolo
authors.affiliation: Department of Chemical Sciences, University of Padova, 35131 Padova, Italy. alessandro.moretto.1@unipd.it and Institute of Biomolecular Chemistry, Padova Unit, CNR, 35131 Padova, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Moretto
mesh_terms: D019817:Benzoic Acid / Q000737:chemistry; D019905:Benzyl Alcohol / Q000737:chemistry; D001894:Borohydrides / Q000737:chemistry; D002384:Catalysis; D003460:Crystallization; D003545:Cysteine / Q000031:analogs & derivatives; D004151:Dipeptides / Q000737:chemistry*; D037741:Fullerenes / Q000737:chemistry*; D007930:Leucine / Q000031:analogs & derivatives; D043942:Nanotubes / Q000737:chemistry*; D010084:Oxidation-Reduction
chemical_list: D001894:Borohydrides; D004151:Dipeptides; D037741:Fullerenes; C025364:sodium borohydride; D019817:Benzoic Acid; D007930:Leucine; D003545:Cysteine; D019905:Benzyl Alcohol