Several 2-nitroalkyl polysaccharide ethers (from pullulan (1), guar (2), agarose (3), inulin (4), cellulose (5), Na-α-polyglucuronate (6) and hydroxyethyl cellulose (7)) were synthesized by reaction with 2-nitro-1-alkenes (2-nitro-1-propene and 2-nitro-1-butene) formed in situ from 2-nitroalkyl acetates. Moderate to high efficiencies are obtained in concentrated aqueous solution/suspension for addition to 1-4 and 7. Analysis of this new class of polysaccharide derivatives with the aid of labeled 2-nitropropyl-2-13C pullulan revealed that the nitrogroup is a mixture of the nitroalkane and nitronic acid tautomers. Grafting of nitroalkenes is observed and, to a lesser extent, additional reactions of the nitro group (formation of carbonyl, oxime and allyl groups) take place. Reduction of 2-nitroalkyl polysaccharide ethers with Na2S2O4or Na2S2O4/NaBH4leads to complex polysaccharide ethers. The products obtained are most likely mixtures of starting material, nitroso compounds, hydroxylamines, hydroxypropyl ethers and sulfamates.
Heeres, A., Spoelma, F. F., Van Doren, H. A., Gotlieb, K. F., Kellogg, R. M., & Bleeker, I. P. (2000). Synthesis and reduction of 2-nitroalkyl polysaccharide ethers. Carbohydrate polymers, 42(1), 33-43. https://doi.org/10.1016/S0144-8617(99)00123-X