Deethylation of Aryl Ethyl Ethers by Boron Tribromide

Boron tribromide is well known as an effective reagent for cleaving methyl aryl ethers.1,2 This procedure suffers from the unpredictable variability in the yield of the phenolic products arising from this cleavage.lb While not reported as a preparative procedure, Egly et al.3 note that boron tribromide cleaves linear alkyl (up to chain length C10) aryl ethers to yield, among a mixture of products, phenols, albeit in low yield.