Methyl and benzyl ethers have been cleaved with a combination of reagents consisting of chlorotrimethylsilane and acetic anhydride containing a catalytic amount of concentrated sulfuric acid. Methylthiomethyl ethers yield the corresponding acetoxymethyl ethers with chlorotrimethylsilane and acetic anhydride. Comparative study with the borontrifluoride etherate and acetic anhydride method of ether cleavage suggests that ...