A highlyenantioselective construction of an all-carbon quaternary stereogenic center at the α-position of malonic diesters has been achieved by Michaeladditionusing phase-transfer catalysis. The reaction of α-monosubstituted malonates with acrylates in the presence of N-(9-anthracenylmethyl)quininium chloride as a phase-transfer catalyst afforded the corresponding α,α-disubstituted malonic diesters
A highly enantioselective α-benzoyloxylation of malonic diester has been achieved by phase-transfercatalysis. The reaction of α-monosubstituted tert-butyl methyl malonate with benzoyl peroxide in the presence of aqueous KOH and N-(9-anthracenylmethyl)cinchoninium chloride afforded the corresponding α,α-disubstituted products in generally excellent chemical yields (up to 99% yield) with high enantioselectivities