• The 7-membered cyclic orthoformates, formed with triethyl or trimethyl orthoformate, are superior reagents for the protection of carbonyl groups as their 2,4-benzodioxepine derivatives. These can be readily cleaved in high yield by Pd-catalyzed hydrogenolysis: Tetrahedron Lett., 30, 4165 (1989); J. Am. Chem. Soc., 116, 558 (1994).
• Has also been employed for the protection of boronic acids, by reaction in THF in the presence of a dehydrating agent, e.g. Na2SO4. These derivatives can be readily cleaved by hydrogenolysis or hydrolysis: Tetrahedron Lett., 37, 6705 (1996).