Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan.
Biomacromolecules. 2012 Sep 10;13(9):2760-8. doi: 10.1021/bm300754u. Epub 2012 Aug 7.
For the first time, 2-O-methyl- (2MC) and 3,6-di-O-methyl-cellulose (36MC) were synthesized via 3-O-allyl- and 3-O-methyl-cellulose, respectively. Position 6 of 3-O-allyl- and 3-O-methyl-cellulose was protected with the 4-methoxytrityl groups. The reaction time and temperature were optimized to achieve a high regioselectivity at C-6 and to prevent the introduction of the 4-methoxytrityl group at C-2 of the polymer. It was found that the substituent at C-3 of 3-O-functionalized celluloses influenced the reactivity of the hydroxyl group at C-6. The structure was characterized by means of (1)H and (13)C NMR spectroscopy of the acetates of 2MC and 36MC. 2MC and 36MC were soluble in water and did not show thermoreversible gelation.
首次通过 3-O-烯丙基- 和 3-O-甲基纤维素分别合成了 2-O-甲基-(2MC)和 3,6-二-O-甲基纤维素(36MC)。用 4-甲氧基三苯甲基保护 3-O-烯丙基- 和 3-O-甲基纤维素中 C-6 的位置。优化了反应时间和温度，以实现 C-6 的高区域选择性，并防止聚合物 C-2 上引入 4-甲氧基三苯甲基。发现 3-O-取代纤维素 C-3 上的取代基影响 C-6 上羟基的反应性。通过 2MC 和 36MC 的醋酸盐的 1H 和 13C NMR 光谱对结构进行了表征。2MC 和 36MC 可溶于水，且不显示热可逆凝胶化。
