A New Method for Alkoxymethyl (MOM or EOM) Protection of Thiol Functionality in Heterocyclic Compounds.

even though the thiol group ismore sensitive than the hydroxyl function to acidic and basicconditions and oxidizing agents. Included among the fewthiol protecting groups described so far is the MOM group.However, to date few procedures have been reported for thepreparation of MOM-protected thiols that do not requirebasic conditions and chloromethyl methyl ether (a carcino-gen) as the substrate. Although there are a few exception37s, an equimolar amount of an acyl halide is needed as anactivating agent