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

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–H2O, we have established the one-pot deprotection under basic conditions [K2CO3 (5 equiv), NH2OH·HCl (5 equiv), and CsF (1 equiv) in MeOH–H2O].