Sustainable Functionalization of 2,3-Dialdehyde Cellulose via the Passerini Three-Component Reaction
Eren Esen, Michaël A. R. Meier
Abstract
Cellulose-based materials have gained more and more interest due to the increasing dependency of mankind on petroleum-based resources, especially during the last few decades. In this work, we report a mild and efficient method to modify 2,3-dialdehyde cellulose (DAC) via the Passerini three-component reaction (P-3CR) in an aqueous medium. Microcrystalline cellulose (MCC) was first oxidized to DAC and further reacted with different renewable carboxylic acids and commercially available isocyanides to obtain molecularly diverse modifications of cellulose with a degree of substitution (DS) ranging from 0.62 to 0.94. Confirmation of the structure of the obtained product was achieved via IR as well as 1H and 13C NMR. Differential scanning calorimetry (DSC) revealed glass transition temperatures (Tg) between 121 and 166 °C, depending on the chosen components for the P-3CR. Thus, we show a novel way to homogeneously modify DAC, which was so far mostly achieved by imine formation.