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Published on: August 17, 2019
Synthesis of cyclic ethers by cyclodehydration of 1,n-diols using heteropoly acids as catalysts
Yufeng Sun1, Yatao Huang1, Minmin Li1
1Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-products Quality and Safety Control in Storage and Transport Process, Ministry of Agriculture and Rural Affairs, Beijing 100193, People's Republic of China.
Abstract:
Heteropoly acids were used as catalysts for cyclodehydration of various 1,n-diols. Cyclodehydration of butane-1,4-diol, pentane-1,5-diol and hexane-1,6-diol catalysed by H3PW12O40 gave tetrahydrofuran, tetrahydropyran and oxepane, respectively. Cyclodehydration of diethylene glycol, triethylene glycol, diethylene glycol monomethyl ether and polyethylene glycol 200 catalysed by H3PW12O40 gave 1,4-dioxane. In particular, cyclodehydration of hexane-1,6-diol gave an excellent yield of oxepane (80%). The selectivity exhibited by the H3PW12O40 catalyst was even better than that exhibited by other reported catalyst systems for similar cyclodehydration reactions.
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