Enantioselective Cascade Reactions of Stable Sulfur Ylides and Nitroolefins through an Axial-to-Central Chirality Transfer Strategy

An enantioselective [4 + 1] annulation/rearrangement
cascade of
stable sulfur ylides and nitroolefins has been developed through an
efficient axial-to-central chirality transfer with the use of a chiral
BINOL-derived sulfide as a reliable stereocontroller. It can provide
pharmaceutically and synthetically important oxazolidinones in high
stereoselectivities (up to 96:4 e.r. and >95:5 d.r.). Moreover,
this
strategy was also successfully applied to the asymmetric [4 + 1]/[3
+ 2] cycloaddition cascade of sulfur ylides with alkene-tethered nitroolefins,
and the corresponding enantioenriched fused heterocycles (up to 87:13
e.r. and >95:5 d.r.) were obtained in good to excellent yields
(54–95%
yields).