Lewis acid promoted carbon–carbon bond forming reac- tions are of great interest because of their unique reactivity and selectivity. Among various Lewis acid catalyzed C–C bond forming reactions, the allylation of carbonyl compounds or their equivalents with allylsilanes is one of the most useful synthetic reactions1 in organic synthesis. gem-Diacetates are ambident substrates containing two types of reactive carbon centers, the carbon atom of a protected aldehyde ...