A Novel Diazo Reagent for Fluorescence Labeling of Carboxyl Groups in Pulp
نویسندگان
چکیده
The reactivity of different diazoalkane reagents was examined using the coupling reaction with methyl β-Dglucopyranosiduronic acid as a model. 9H-Fluoren-2-yl-diazomethane (FDAM), prepared from its precursor 9H-fluoren2-carbaldehyde hydrazone by MnO2 oxidation, was found suitable as a new labeling agent for carboxyl groups in carbohydrate materials. The reaction with methyl β-D-glucopyranosiduronic acid showed FDAM to be highly reactive and specific for carboxyl groups. The new label will be used in pre-column fluorescence derivatization of pulp with low contents in carboxyl groups to determine these functionalities in dependence on the molecular weight distribution by a modified GPC-system with fluorescence-, MALLSand RIdetection in DMAc / LiCl.
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