title: Synthesis of amide-functionalized cellulose esters by olefin cross-metathesis.
abstract: Cellulose esters with amide functionalities were synthesized by cross-metathesis (CM) reaction of terminally olefinic esters with different acrylamides, catalyzed by Hoveyda-Grubbs 2nd generation catalyst. Chelation by amides of the catalyst ruthenium center caused low conversions using conventional solvents. The effects of both solvent and structure of acrylamide on reaction conversion were investigated. While the inherent tendency of acrylamides to chelate Ru is governed by the acrylamide N-substituents, employing acetic acid as a solvent significantly improved the conversion of certain acrylamides, from 50% to up to 99%. Homogeneous hydrogenation using p-toluenesulfonyl hydrazide successfully eliminated the α,β-unsaturation of the CM products to give stable amide-functionalized cellulose esters. The amide-functionalized product showed higher Tg than its starting terminally olefinic counterpart, which may have resulted from strong hydrogen bonding interactions of the amide functional groups.
authors.affiliation: Macromolecules and Interfaces Institute, Virginia Tech, Blacksburg, VA 24061, United States; Department of Sustainable Biomaterials, Virginia Tech, Blacksburg, VA 24061, United States.
authors.forename: Xiangtao
authors.initials: X
authors.lastname: Meng
authors.affiliation: Macromolecules and Interfaces Institute, Virginia Tech, Blacksburg, VA 24061, United States; Department of Sustainable Biomaterials, Virginia Tech, Blacksburg, VA 24061, United States. Electronic address: kjedgar@vt.edu.
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Edgar
mesh_terms: D000475:Alkenes / Q000737:chemistry*; D000577:Amides / Q000737:chemistry; D002384:Catalysis; D002482:Cellulose / Q000737:chemistry*; D004952:Esters; D006865:Hydrogenation; D009682:Magnetic Resonance Spectroscopy; D012428:Ruthenium / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D014105:Tosyl Compounds / Q000737:chemistry
chemical_list: D000475:Alkenes; D000577:Amides; D004952:Esters; D014105:Tosyl Compounds; D012428:Ruthenium; D002482:Cellulose; C002030:4-toluenesulfonyl hydrazide
keywords: Acetic acid; Amides; Cellulose esters; Click reactions; Olefin metathesis; Solvents