In some cases, an epoxide is used instead of the alcohol; or an acid halide or anhydride replaces the acid. Less often, an alkyl or aryl halide is treated with a carboxylate salt. But these methods ...

THE cleaving of an ether usually requires the use of a vigorous reagent such as an anhydrous mineral acid, an organic acid halide or anhydride, a Lewis acid, or an organometallic compound.