Stereochemical control on the Michael addition of chiral 1,3-oxazolidine-2-thiones to N-crotonyl 1,3-oxazolidin-2-ones

Addition of both antipodes of 4-phenyl 1,3-oxazolidine-2-thione to 4-substituted N-crotonyl 1,3-oxazolidin-2-ones furnished Michael addition products. A perfect match occurred when both Michael donor and acceptor possessed the same stereochemistry and a mismatch when they had opposite stereochemistries. The newly created stereochemical center was shown to be governed by the Michael donor and not by the acceptor.