Exploiting Differences in Solution vs Solid-Supported Reactivity for the Synthesis of Sulfonic Acid Derivatives

Abstract

We describe a method herein for the protection of aryl and alkyl sulfonates during synthesis which employs commercially available Wang or MBOH resin, both of which terminate as benzyl alcohols, as both a protecting group and “traceless” linker. Given the known instability of benzylic sulfonate esters to nucleophilic displacement in solution, this linkage is surprisingly stable: no loss of either aryl or alkyl sulfonates is observed when the resin is exposed to a wide variety of organic bases and solvents at room temperature. Further elaboration of the resin-bound sulfonates via Suzuki coupling is also described.