Benzenesulfonyl Chlorides: Alternative Coupling Partners for Regiocontrolled Palladium-Catalyzed Direct Desulfitative 5-Arylation of Furans

The reactivity of furan derivatives in palladium-catalyzed desulfitative arylation was studied. Alkyl-substituted furan derivatives were successfully coupled with a variety of benzenesulfonyl chlorides using a phosphine-free catalyst; regioselective arylation at C5 of the furan was observed in all cases. This reaction tolerates a wide variety of substituents on the benzenesulfonyl derivative. It should be noted that even bromo-and iodobenzenesulfonyl chlorides were successfully coupled with furan derivatives without cleavage of the C-Br or C-I bonds, thus allowing further transformations. The use of these reactants demonstrates the potential of benzenesulfonyl chlorides as coupling partners to access to functionalized 5-arylfurans.