Synthesis of (13)C-perlabeled cellulose with more than 99% isotopic enrichment by a cationic ring-opening polymerization approach.
(13)C-Perlabeled cellulose was obtained in a seven-step approach from (13)C(6)-labeled d-glucose with a cationic ring-opening polymerization as the key step. Isopropylidene protection, benzylation of the remaining free 3-O-position and subsequent deprotection afforded 3-O-benzyl-(13)C(6)-glucose (2). Regioselective bis-pivaloylation followed by subsequent ortho-esterification provided the precursor for the cationic ring-opening polymerization, 3-O-benzyl-(13)C(6)-glucopyranose 1,2,4-orthopivalate (4). The actual polymerization step gave a stereo- and regioregular (13)C-perlabeled (1-->4)-beta-glucopyranan derivative, which was deprotected into fully labeled (13)C-cellulose, as the cellulose II allomorph with a DP of 40, in an overall 28% yield. All reaction steps were optimized beforehand with nonlabeled compounds toward high yields and high reproducibility and the final compound was comprehensively analytically characterized.
Adelwöhrer
Christian
C
Department of Chemistry, University of Natural Resources and Applied Life Sciences Vienna, Vienna, Austria.
Takano
Toshiyuki
T
Nakatsubo
Fumiaki
F
Rosenau
Thomas
T
D002247:Carbon Isotopes / Q000737:chemistry*; D002482:Cellulose / Q000138:chemical synthesis*; D002855:Chromatography, Thin Layer; D004951:Esterification; D008401:Gas Chromatography-Mass Spectrometry; D009682:Magnetic Resonance Spectroscopy; D011108:Polymers / Q000737:chemistry*; D014961:X-Ray Diffraction
D002247:Carbon Isotopes; D011108:Polymers; D002482:Cellulose