The diastereoselective Michael addition of lithiated enantiopure
sulfonates to nitroalkenes is described. High asymmetric inductions
were obtained by using 1,2:5,6-di-O-isopropylidene-α-d-allofuranose as a cheap and easily available
chiral auxiliary. Racemization-free cleavage of the auxiliary led
to α,β-disubstituted γ-nitro methyl sulfonates.
A change of the cleavage conditions resulted in α,β-disubstituted β-alkoxycarbonyl
sulfonates via the Meyer reaction (de ≥ 98%,
ee ≥ 98%).
Michael additions - nitroalkenes - sulfonates - chiral auxiliaries - carbohydrates - Meyer
reaction