[F:1][C:2]1[C:10]([F:11])=[C:9](C(O)=O)[C:8]([F:15])=[C:7]([F:16])[C:3]=1[C:4]([OH:6])=[O:5]>O>[F:1][C:2]1[C:10]([F:11])=[CH:9][C:8]([F:15])=[C:7]([F:16])[C:3]=1[C:4]([OH:6])=[O:5]80 g of 80% strength by weight 2,3,5,6-tetrafluoroterephthalic acid (containing 8% by weight of sulfuric acid and 12% by weight of water) were mixed with 300 g of water in a 0.6 l enamelled autoclave and heated for 40 hours at 130° C. After cooling to 20° C. and depressurizing, the suspension then present was filtered, washed with 60 g of water and the white solid was dried. 42 g of 2,3,5,6-tetrafluorobenzoic acid having a content of 98% by weight and a melting point of 151° C. were obtained.
Wird geladen…