4-(tert-Butyldimethylsilyloxy)benzylidene acetal: a novel benzylidene-type protecting group for 1,2-diols

Abstract A novel 1,2-diol-protecting group, p -silyloxybenzylidene group, has been developed. In addition to the stepwise deprotection conditions including desilylation and the subsequent acidic hydrolysis of the p -hydroxybenzylidene group in AcOH–THF–H 2 O, we have established the one-pot deprotection under basic conditions [K 2 CO 3 (5 equiv), NH 2 OH·HCl (5 equiv), and CsF (1 equiv) in MeOH–H 2 O].