Abstract
Summary: Novel 2,3‐O‐hydroxyethyl‐ and 2,3‐O‐hydroxypropyl cellulose products were synthesized by heterogeneous etherification of 6‐O‐(4‐monomethoxytrityl) cellulose (MMTC). Due to the very hydrophobic character of MMTC, the reaction was successful in the presence of anionic and non‐ionic detergent in the reaction mixture yielding the 2,3‐O‐cellulose ethers with a molar degree of substitution (MS) varying between 0.25 and 2.00 after detritylation. The products were characterized by means of ^1^H and ^13^C NMR spectroscopy including two‐dimensional methods. The 2,3‐O‐hydroxypropyl cellulose samples are soluble in water at a MS as low as 0.8. The spectroscopic studies showed that the unusual solubility results from a preferred substitution of hydroxy groups of the anhydroglucose unit while the newly formed hydroxy moieties are included in the reaction to a minor extent only. In contrast, conventionally synthesized hydroxypropyl cellulose is soluble in water starting at a MS of about 4.0 because of the formation of oxyethylene side chains.
^13^C DEPT 135 NMR spectrum of 2,3‐O‐hydroxypropyl cellulose.
image^13^C DEPT 135 NMR spectrum of 2,3‐O‐hydroxypropyl cellulose.