The C-O bond of phenol can be activated by reaction with arylsulfonyl chlorides to yield the corresponding arylsulfonates that can be used as electrophilic partners in subsequent reactions. Arylsulfonates can be conveniently synthesized from inexpensive phenol derivatives and sulfonyl chlorides. Moreover, their crystalline nature makes arylsulfonates easier than other electrophiles to purify and store over a long period of time. Although arylsulfonates are inferior to triflates in terms of electrophilicity, triflates are better leaving groups compared to sulfonates; arylsulfonates however have greater economical advantages over triflates. Facile synthesis of different arylsulfonates from various arylsulfonyl chlorides and phenol are reported. What is unique about the synthesis is that very good to excellent yields of arylsulfonates were obtained without the use of column chromatography. A more efficient purification technique was developed based on recrystallization. Using 2,4-dinitrophenyl 4-methylbenzenesulfonate and various amines, initial experiments have shown greater regioselectivity for the SNAr products.
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