Aldol reaction of 4-trimethylsiloxy-6-methylene-1,3-dioxines with chiral aldehydes: Enantioselective synthesis of 1,3-dioxin-4-ones having a 2,3-dihydroxylated alkyl group at the 6-position
A novel enantioselectivesynthesis of 1,3-dioxin-4-ones having a 2,3-dihydroxylated alkyl group at the 6-position has been accomplished by titaniumtetrachloride-mediatedaldolcondensation of silyl enol ethers derived from the 6-alkylated dioxinones with chiral 2-benzyloxypropanal. The keto group of the corresponding β-keto esters obtained after cleavage of the acetal function affords, by 1,3-syn