One-Pot Bi(OTf)₃-Catalyzed Oxidative Deprotection of tert-Butyldimethyl Silyl Ethers with TEMPO and Co-Oxidants

Abstract

A sequential one-pot synthesis for the oxidation of primary and secondary tert-butyldimethylsilyl (TBDMS) ethers, using catalytic amounts of metal triflates and TEMPO in combination with PhIO or PhI(OAc)₂ in THF or acetonitrile, is described. Acid-sensitive protecting groups such as methylidene, isopropylidene, acetals, and Boc are unaffected under the reaction conditions. Another feature of this procedure is its high selectivity for TBDMS ethers over tert-butyldiphenylsilyl ethers and of aliphatic TBDMS groups over phenolic TBDMS groups.

Key words

bismuth(III) triflate - carbonyl compounds - oxidation - silyl ethers - TEMPO

References and Notes

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16

In the presence of PhIO/TEMPO system, diacetone galactose gave mainly polar products.