Synthesis of xylan carbonates – An approach towards reactive polysaccharide derivatives showing self-assembling into nanoparticles. (1st August 2018)

• Record Type: Journal Article
• Authors: Gericke, Martin; Gabriel, Lars; Geitel, Katja; Benndorf, Stefan; Trivedi, Poonam; Fardim, Pedro; Heinze, Thomas
• Is Part Of: Carbohydrate polymers. Volume 193(2018)
• Page Start: 45
• Page End: 53
• Publication Date: 2018-08-01
• Subjects: Polysaccharides -- Xylan derivatization -- Xylan carbonates -- Nanoparticles -- Ionic liquids -- Substituent distribution pattern; Polysaccharides -- Periodicals; Polysaccharides -- Periodicals; Polysaccharides -- Périodiques; Electronic journals; 547.78
• DOI: 10.1016/j.carbpol.2018.03.083
• Languages: English
• ISSNs: 0144-8617

Abstract

Highlights: Novel xylan phenylcarbonates with a degree of substitution up to 2.0 were prepared in different homogeneousreaction media. The reaction efficiency and degree of substitution greatly depended on the reaction medium and reaction conditions. A predominant substitution at the position C-3 was revealed by 1D- and 2D-NMR spectroscopy. Xylan phenyl carbonates form well-defined nanoparticles with activated moieties that react with nucleophilic compounds. Abstract: Xylan phenyl carbonate (XPC) derivatives were prepared and characterized comprehensively. By conversion of xylan with phenyl chloroformate either in dipolar aprotic solvents with LiCl or in an ionic liquid, XPC with degrees of substitution (DS) of up to 2.0, i.e., fully functionalized derivatives, could be obtained. The synthesis was studied with respect to the influence of different reaction parameters. It was found that the reaction medium as well as the type of starting xylan strongly affected the efficiency of the derivatization. The derivatives obtained were characterized by FT-IR- and NMR spectroscopy. Surprisingly, it was found that C-3 is the most reactive position in this particular reaction while substitution in position C-2 only occurred if the neighboring position C-3 already carried a phenyl carbonate group. XPC were found to form spherical nanoparticles (NP) of well-defined shape with diameters around 158 nm. These materials possess unique potential as activated NP for advanced applications.