Arylation of benzazoles at the 4 positions by activation of their 2-methylsulfinyl groups

Abstract

Treatment of 2-methylsulfinylbenzazoles with triflic anhydride in the presence of phenols yields the corresponding 4-(p-hydroxyphenyl)-2-methylsulfanylbenzazoles. This regioselective dehydrative C–H/C–H coupling arylation represents a rare example of functionalizations on the benzene rings of benzo-fused azoles.