W. Dmowski, J. Wielgat
Dec 1, 1987
Citations
0
Influential Citations
12
Citations
Journal
Journal of Fluorine Chemistry
Abstract
Abstract Fluorination of tetrachlorophthalic anhydride 1 or tetrachlorophthalic acid hemihydrate 4 with an excess of sulphur tetrafluoride provides an efficient one-step synthesis of 4,5,6,7-tetrachloro-1,1,3,3-tetrafluoro-1,3-dihydroisobenzofuran 2 . 3,4,5,6-Tetrachloro-2-(trifluoromethyl)benzoyl fluoride 3 is formed as a side product. A method for the quantitative removal of fluoride 3 and its isolation as 3,4,5,6-tetrachloro-2-(trifluoromethyl)benzoic acid 6 has been developed. The reduced SF4 to 1 ratio gives a mixture of 2 and 4,5,6,7-tetrachloro-3,3-difluoro-3-hydroisobenzofuranone 5 .