| 摘要 |
4-(2-Thenoyl)-2,3-dichlorophenoxyacetic acid of the polymorphic modification B, characterised by an infrared spectrum having strong absorption bands at 1725 and 1418 cm<-1> and a very weak absorption band at 1180 cm<-1>, and a melting point, determined by differential thermoanalysis, of 152 DEG C. This modification B can be prepared by recrystallising the modification A either a) slowly or rapidly from non-polar solvents, or b) rapidly from hot chloroform or ethylene dichloride. |
