Chemoselective Transformations of Aromatic Methoxymethyl Ethers Using Trialkylsilyl Triflate and 2,2'-Bipyridyl

Aromatic methoxymethyl (MOM) ethers behave differently from aliphatic MOM ethers upon treatment with trialkylsilyl triflate (R₃SiOTf) and 2,2'-bipyridyl. The aromatic MOM ethers are first converted to silyl ethers and subsequently deprotected by hydrolysis to give the mother alcohols when the R₃SiOTf used is trimethylsilyl triflate (TMSOTf). Conversely, direct conversion of aromatic MOM ethers to aromatic triethylsilyl (TES) ethers is possible when the R₃SiOTf used is triethylsilyl triflate (TESOTf).