Cleavage of aryl alkyl ethers was conducted in a one-pot onestage manner by mixing the ethers, aluminum and iodine in acetonitrile without the in situ preparation of aluminum triiodide in advance. For ethers bearing acid-labile functional groups such as allyl, alkenyl and carbonyl, an acid scavenger (calcium oxide, 1,3-diisopropylcarbodiimide or dimethyl sulfoxide) was used to prevent side-reactions. This one-pot protocol is efficient and convenient for the removal of methyl, ethyl, isopropyl and tert-butyl groups from typical aryl alkyl ethers, catechol monomethyl and dimethyl ethers, and is compatible with a variety of functional groups including alkenyl, alkyl, allyl, amido, cyano, formyl, halogen, keto and nitro group. Methyl 2-anisate and eugenol acetate were exhaustively deprotected by the method that afforded salicylic acid and hydroxychavicol, respectively.

Aluminum triiodide is harnessed by N,N-dimethylformamide dimethyl acetal (DMF-DMA) for the selective cleavage of ethers via neighboring group participation. Various acid-labile functional groups, including carboxylate, allyl, tert-butyldimethylsilyl (TBS), and tert-butoxycarbonyl (Boc), suffer the conditions intact. The method offers an efficient approach to cleaving catechol monoalkyl ethers and to uncovering phenols from acetal-type protecting groups such as methoxymethyl (MOM), methoxyethoxymethyl (MEM), and tetrahydropyranyl (THP) chemoselectively.

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