Reagent for protection of alcohols, compare Chlorotriphenyl-methane, as their dimethoxytrityl (Dmt) ethers. Mono-, di- and trimethoxytrityl chlorides form ethers of increasing acid-lability, each MeO group increasing the rate of cleavage by ca x10: J. Am. Chem. Soc., 84, 430 (1962); 85, 3821 (1963). The group is introduced e.g. by reaction with the alcohol in pyridine solution. For use of DMAP as catalyst, see: J. Am. Chem. Soc., 104, 1316 (1982), or of silver nitrate: Can. J. Chem., 60, 1106 (1982). For selective protection and deprotection procedures for SH and OH groups in nucleoside derivatives, see: Synlett, 83 (1993). In a comparison with Mmt for N-protection during solid-phase peptide synthesis, the N-Mmt group was found to survive intact whereas N-Dmt derivatives decomposed slowly in protic solvents: Tetrahedron. Lett., 39, 1733 (1998).
