| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for producing 3,4-alkylenedioxythiophene-2,5-dicarboxylic acid derivatives having general formulas IV and V. <P>SOLUTION: In the first stage, 3,4-dihydroxythiophene-2,5-dicarboxylic acid ester is produced from a thio diacetic diester and an oxalic diester as starting materials in the presence of an alkali metal dialkoxide. In the second stage, the esters are alkylated by using a dihaloalkane to 3,4-alkylenedioxythiophene-2,5-dicarboxylic ester. In the third stage, by saponification, a 3,4-alkylenedioxythiophene-2,5-dicarboxylic acid is produced. At least two stages within the three stages are characterized by being carried out without isolating any intermediates. The method provides a target product with high purity and yields. <P>COPYRIGHT: (C)2012,JPO&INPIT |
