Synthesis of polysulfonates and polysulfonamides from 7,7-dimethyl-7H-dibenzo[c,h]xanthene-5,9-disulfonyl chloride

Abstract

Treatment of 7,7-dimethyl-7H-dibenzo[c,h]xanthene with chlorosulfonic acid leads to the formation of the mono-, di- and tetrasulfonyl chloride derivatives. The 5 and 9 positions of 7,7-dimethyl-7H-dibenzo[c,h]xanthene were found to be most active toward electrophilic sulfonation. Polysufonates and polysulfonamides prepared from 7,7-dimethyl-7H-dibenzo[c,h]xanthene-5,9-disulfonyl chloride exhibit glass transition temperatures above 200°C and show little weight loss at temperatures to 350°C.