Claims
- 1. A process for preparing a 2-hydroxymethyl-2,3-dihydro-thieno[3,4-b][1,4]dioxine-5,7-dicarboxylic acid diester comprising the reaction of the alkali salt of 3,4-dihydroxythiophene-2,5-dicarboxylic acid diester and epihalohydrin in a molar ratio in the range of 1.01 to 1.4 in a polar solvent or mixture of polar solvent at a temperature between −20° C. to the boiling point of the polar solvent or polar solvent mixture.
- 2. Process according to claim 1, wherein said process is carried out at a temperature between 45° C. and the boiling point of the polar solvent or polar solvent mixture used.
- 3. Process according to claim 1, wherein said polar solvent is selected from the group consisting of DMF, DMA, DMSO and NMP or mixtures thereof.
- 4. Process according to claim 1, wherein epihalohydrin is epibromohydrin.
- 5. Process according to claim 1, wherein said 3,4-dihydroxythiophene-2,5-dicarboxylic acid diester has ester groups selected from the group consisting of methyl, ethyl, n-propyl and n-butyl.
Priority Claims (1)
Number |
Date |
Country |
Kind |
02100490 |
May 2002 |
EP |
|
Parent Case Info
The application claims the benefit of U.S. Provisional Application No. 60/382,576 filed May 22, 2002, which is herein incorporated by reference.
US Referenced Citations (3)
Number |
Name |
Date |
Kind |
5111327 |
Blohm et al. |
May 1992 |
A |
6369239 |
Rauchschwalbe et al. |
Apr 2002 |
B2 |
6528662 |
Jonas |
Mar 2003 |
B2 |
Non-Patent Literature Citations (1)
Entry |
Search Report for EP 02 10 0490 (Oct. 16, 2002). |
Provisional Applications (1)
|
Number |
Date |
Country |
|
60/382576 |
May 2002 |
US |