J. Porwisiak, W. Dmowski
1991
Citations
0
Influential Citations
8
Citations
Journal
Journal of Fluorine Chemistry
Abstract
Abstract Treatment of dichloro- or dibromopyromellitic acids 1 or 2 with a mixture of sulphur tetrafluoride and hydrogen fluoride gave the respective 4,8-dihalo-1,1,3,3,5,5,7,7-octafluoro-1,3,5,7-tetrahydrobenzo[1,2-c:4,5-c′]difurans (3) and (4) in high yields. Dichloro compound 3 easily undergoes halogen-exchange with potassium fluoride to give perfluoro-1,3,5,7-tetrahydrobenzo[1,2-c:4,5-c′]difuran (5). Reduction of dibromo-compound 4 with lithium aluminium hydride gave, depending on the reaction conditions, 1,1,3,3,5,5,7,7-octafluoro-1,3,5,7-tetrahydrobenzo[1,2-c:4,5-c′]difuran (6) or 4-bromo-1,1,3,3,5,5,7,7-octafluoro-1,3,5,7-tetrahydrobenzo[1,2-c,4,5-c′]difuran (7).