Monosaccharides as Versatile Units for Water-Soluble Supramolecular Polymers

• Published in: Chemistry : a European journal 2016-03, Vol.22 (13), p.4608-4615
• Main Authors: Leenders, Christianus M. A., Jansen, Gijs, Frissen, Martijn M. M., Lafleur, René P. M., Voets, Ilja K., Palmans, Anja R. A., Meijer, E. W.
• Format: Article
• Language: English
• Subjects: Aggregates; Benzamides - chemistry; Benzene; Bonding; Boron Compounds - chemistry; boronic acids; Chains (polymeric); Chemistry; Compatibility; Covalence; Dynamics; Fluorescence; Fluorescence microscopy; fluorescence spectroscopy; Galactose; Glucose; Imaging; Libraries; Mannose; Microscopy; Microscopy, Fluorescence; Monosaccharides; Monosaccharides - chemistry; Polymers; Polymers - chemistry; Saccharides; Self assembly; Spacer; Spacers; supramolecular chemistry; Supramolecular polymers; Water - chemistry
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.201504762

We introduce monosaccharides as versatile water‐soluble units to compatibilise supramolecular polymers based on the benzene‐1,3,5‐tricarboxamide (BTA) moiety with water. A library of monosaccharide‐based BTAs is evaluated, varying the length of the alkyl chain (hexyl, octyl, decyl and dodecyl) separating the BTA and saccharide units, as well as the saccharide units (α‐glucose, β‐glucose, α‐mannose and α‐galactose). In all cases, the monosaccharides impart excellent water compatibility. The length of the alkyl chain is the determining factor to obtain either long, one‐dimensional supramolecular polymers (dodecyl spacer), small aggregates (decyl spacer) or molecularly dissolved (octyl and hexyl) BTAs in water. For the BTAs comprising a dodecyl spacer, our results suggest that a cooperative self‐assembly process is operative and that the introduction of different monosaccharides does not significantly change the self‐ assembly behaviour. Finally, we investigate the potential of post‐assembly functionalisation of the formed supramolecular polymers by taking advantage of dynamic covalent bond formation between the monosaccharides and benzoxaboroles. We observe that the supramolecular polymers readily react with a fluorescent benzoxaborole derivative permitting imaging of these dynamic complexes by confocal fluorescence microscopy. Sugar‐coating BTAs: Functionalising the periphery of benzene‐1,3,5‐tricarboxamide (BTA) with monosaccharides affords high aspect ratio supramolecular polymers in water, which are readily post‐modified using benzoxaboroles by dynamic covalent chemistry (see figure).