De Oliveira Silva A, Harper JL, Fuhr KN, Lalancette RA, Cheong PHY, Brenner-Moyer SE. DyKAT by DiCat: Stereoconvergent Dienamine-Catalyzed Claisen Rearrangements.
J Org Chem 2022;
87:10105-10113. [PMID:
35881006 DOI:
10.1021/acs.joc.2c01079]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This Claisen rearrangement establishes the feasibility of DyKAT of γ-epimeric enals via dienamine formation to afford enantioenriched products. γ-Aryl and -alkyl enals, and exocyclic enals that introduce quaternary centers, are all amenable substrates. Products are readily converted into pyrrolidines or cyclopentenols. Notably, a reactive dienamine intermediate has been isolated from a catalytic reaction, fully characterized, and converted to product upon reexposure to reaction conditions. Product configuration arises from a directing C-H···π interaction in the transition state.
Collapse