1,6-Addition Reaction of 5<i>H</i>-Oxazol-4-ones to Conjugated Dienones Catalyzed by Chiral Guanidines

Abstract

Abstract A chiral guanidine-catalyzed 1,6-addition reaction of 5H-oxazol-4-ones to α,β,γ,δ-diunsaturated ketones is described in this study. The addition reaction proceeded regiospecifically to yield a 1,6-addition product with high enantioselectivity. Obtained adducts of the 1,6-addition could be converted into the corresponding chiral 7-oxo-α-hydroxy acid derivatives or chiral α-homoallylic-hydroxy acid derivatives via 2nd generation Grubbs catalyst-mediated olefin metatheses.