A strategy of ketalization for the catalytic selective dehydration of biomass-based polyols over H-beta zeolite

作者：Che, Penghua; Lu, Fang^*; Si, Xiaoqin; Ma, Hong; Nie, Xin; Xu, Jie^*

来源：Green Chemistry, 2018, 20(3): 634-640.

DOI：10.1039/c7gc03248j

• SORBITOL DEHYDRATION
• DIMETHYL CARBONATE
• SUGAR ALCOHOLS
• ACID SITES
• ISOSORBIDE
• CONVERSION
• CELLULOSE
• GLYCEROL
• TEMPERATURE
• DERIVATIVES

Biomass contains plentiful hydroxyl groups that lead to an oxygen-rich structure compared to petroleum-based chemicals. Dehydration is the most energy-efficient technique to remove oxygen; however, multiple similar vicinal hydroxyl groups in sugar alcohols impose significant challenges for their selective dehydration. Here, we present a novel strategy to control the etherification site in sugar alcohols by the ketalization of the vicinal-diol group for the highly selective formation of tetrahydrofuran derivatives. A ketone firstly reacts with terminal vicinal hydroxyl groups to form the 1,3-dioxolane structure. This structure of the constrained 1,3-dioxolane ring would improve the accessibility of reactive groups to facilitate intramolecular etherification. As a better leaving group than water, the ketone can also promote intramolecular etherification. Consequently, a range of tetrahydrofuran derivatives are produced in excellent yields with the H-beta zeolite catalyst under mild reaction conditions. This strategy opens up new opportunities for the efficient upgrading of biomass via the modification or protection of hydroxyl groups.

• 出版日期2018-2-7
• 单位中国科学院大学; 中国科学院大连化学物理研究所; 催化基础国家重点实验室