学術雑誌論文 Rapid Benzylation of Cellulose in Tetra-n-butylphosphonium Hydroxide Aqueous Solution at Room Temperature

Abe, Mitsuru  ,  Sugimura, Kazuki  ,  Nishiyama, Yoshiharu  ,  Nishio, Yoshiyuki

5 ( 6 )  , pp.4505 - 4510 , 2017-04-25 , American Chemical Society (ACS)
ISSN:2168-0485
内容記述
We found a very fast benzylation of cellulose in a tetraalkyl-onium hydroxide solvent system, 47% tetra-n-butylphosphonium hydroxide aqueous solution. Benzyl cellulose (BC) with a degree of substitution (DS) above 2.5 was obtained within 10 min at ambient temperature (20–25 °C) using ∼9 mol equiv of benzyl bromide to the anhydroglucose unit. The highly efficient benzylation proceeded in the transiently stabilized emulsion state of the reaction system, and the product precipitated out as a solid sediment in the liquid medium. At 20 °C, the benzyl DS was 1.92 after 2 min, and reached 2.40 and 2.53 after 5 and 10 min, respectively. The reaction temperature had a negative correlation with the maximum DS in the explored range of 10–50 °C. No significant degradation of the cellulosic main chain was observed for highly substituted BCs (DS > 2.5). The solubility of BC in common organic solvents was also examined for products with various DSs.
本文を読む

http://repository.kulib.kyoto-u.ac.jp/dspace/bitstream/2433/226163/1/acssuschemeng.7b00492.pdf

このアイテムのアクセス数:  回

その他の情報