Tetrahydropyranyl ethers (THP groups) and 1-ethoxyethyl ethers (EE groups) are removed upon refluxing in 95% EtOH or Me2CO–H2O (95:5) in the presence of a catalytic amount of copper(II) chloride dihydrate (2–5 mol%).
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However, we found that tert-butyldimethylsilyl(TBDMS) ethers were also hydrolyzed under these conditions.
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