| 摘要 |
Purification of an optionally 3- and 3,4-substituted thiophene (I) comprises precipitating (I), which is liquid at room temperature, as solid from a solution in a solvent or solvent mixture by cooling introducing it into a cooled solvent (mixture) or cooled solution of the same (I) at a temperature below the melting point of (I) and separation. Purification of an optionally 3- and 3,4-substituted thiophene of formula (I) comprises precipitating (I), which is liquid at room temperature, as solid from a solution in a solvent or solvent mixture by cooling introducing it into a cooled solvent (mixture) or cooled solution of the same (I) at a temperature below the melting point of (I) and separation: [Image] R 1>, R 2>H, optionally substituted 1-20C (oxy)alkyl, optionally with 1-5 O and/or S atoms in the chain, or together an optionally substituted 1-20C dioxyalkylene or 1-20 C dioxyarylene group. Independent claims are included for: (1) purified (I) with a purity of not less than 99.50%; (2) (I) with a purity of not less than 99.50%. |
