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Synthesis of cyclic ethers by cyclodehydration of 1,n-diols using heteropoly acids as catalysts.

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.

SUBMITTER: Sun Y

PROVIDER: S-EPMC6170547 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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Synthesis of cyclic ethers by cyclodehydration of 1,n-diols using heteropoly acids as catalysts.

Sun Yufeng Y Huang Yatao Y Li Minmin M Lu Jia J Jin Nuo N Fan Bei B

Royal Society open science 20180926 9

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, cycl ...[more]

PMID: 30839702

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