Kinetic Resolution of Tertiary Alcohols by Chiral DMAP Derivatives: Enantioselective Access to 3-Hydroxy-3-substituted 2-Oxindoles.
Hiroki MandaiRyuhei ShiomotoKazuki FujiiKoichi MitsudoSeiji SugaPublished in: Organic letters (2020)
We developed an efficient acylative kinetic resolution of 3-hydroxy-3-substituted 2-oxindoles by a chiral DMAP derivative having a 1,1'-binaphthyl with two tert-alcohols units. A wide range of 3-hydroxy-3-substituted oxindoles having various functional groups were efficiently resolved (14 examples, up to s = 60) in the presence of 1 mol % of catalyst within 3-9 h. Multigram-scale reactions (10 g) also proceeded with a high s-factor (s = 43) within 5 h.