Control of Chemo-, Regio-, and Enantioselectivity in Copper Hydride Reductions of Morita-Baylis-Hillman Adducts.

Nonracemically ligated copper hydride can be used to effect tandem SN2'/1,2-reductions of racemic Morita-Baylis-Hillman (MBH) acetates to access enantioenriched chiral allylic alcohols with defined olefin geometry. MBH esters, including those with β-substitution, can be transformed to stereodefined enoates by taking advantage of a bulky, oligomeric, in situ generated trialkoxysiloxane leaving group. Finally, an atypical conversion of easily arrived at MBH alcohol derivatives to nonracemic allylic alcohols is disclosed.