3,4-二氧-羟甲基-乙基噻吩的合成

Synthesis of 3,4-Hydroxymethyl-Ethylene dioxythiophene

摘要: 3,4-二羟基噻吩-2,5-二羧酸甲酯在N,N-二甲基甲酰胺(DMF)/三乙胺的体系中与环氧溴丙烷反应可生成3,4-二氧-羟甲基-乙基噻吩-2,5-二羧酸甲酯，后者在碱性水介质中经水解反应生成3,4-二氧-羟甲基-乙基噻吩-2,5-二羧酸，其在三乙醇胺中经高温脱羧生成3,4-二氧-羟甲基-乙基噻吩，产物是3,4-二氧-羟甲基-乙基噻吩与3,4-二氧-羟丙基噻吩的二元混合物，两者的质量比是6∶1。

Abstract: Dimethyl 3,4-dioxylthiophene-2,5-dicarboxylate reacted with epibromohydrin in N,N-dimethylformamide (DMF)/triethylamine to afford dimethyl 2-(hydroxymethyl)-2,3-dihydrothieno［3,4-b］-1,4- dioxine-5,7-dicarboxylate, which was saponified in aqueous KOH to form dimethyl 2-(hydroxymethyl)-2,-dihydrothieno ［3,4-b］-1,4-dioxine-5,7-dicarboxylic-acid.After decarboxylation in triethanolamine, 3,4-hydroxymethyl-ethylenedioxythiophene was obtained, which is a mixture of 2,3-dihydrothieno［3,4-b］-1,4-dioxin-2-yl methanol and 3,4-dihydro-2H-thieno［3,4-b］-1,4-dioxepin-3-ol and their ratio was 6∶1.