title: Olefin cross-metathesis as a source of polysaccharide derivatives: cellulose ω-carboxyalkanoates.
abstract: Cross-metathesis has been shown for the first time to be a useful method for the synthesis of polysaccharide derivatives, focusing herein on preparation of cellulose ω-carboxyalkanoates. Commercially available cellulose esters were first acylated with 10-undecenoyl chloride, providing esters with olefin-terminated side chains. Subsequent cross-metathesis of these terminal olefin moieties with acrylic acid was performed in solvents including acrylic acid, THF, and CH2Cl2. Complete conversion to discrete, soluble cross-metathesis products was achieved by using the Hoveyda-Grubbs second generation ruthenium catalyst and an excess of acrylic acid. Oligomerization during storage, caused by a free radical mechanism, was observed and successfully suppressed by the addition of a free radical scavenger (BHT). Furthermore, the cross-metathesis products exhibited glass transition temperatures (Tg) that were at least 50 °C higher than ambient temperature, supporting the potential for application of these polymers as amorphous solid dispersion matrices for enhancing drug aqueous solubility.
authors: Macromolecules and Interfaces Institute, ‡Department of Sustainable Biomaterials, and §Department of Chemistry, Virginia Tech , Blacksburg, Virginia 24061, United States.
authors: Xiangtao
authors: X
authors: Meng
authors: John B
authors: JB
authors: Matson
authors: Kevin J
authors: KJ
authors: Edgar
mesh_terms: D000473:Alkanes / Q000032:analysis / Q000737:chemistry*; D000475:Alkenes / Q000032:analysis / Q000737:chemistry*; D002482:Cellulose / Q000032:analysis / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D011134:Polysaccharides / Q000032:analysis / Q000737:chemistry*
chemical_list: D000473:Alkanes; D000475:Alkenes; D011134:Polysaccharides; D002482:Cellulose