Enantio-, Diastereo-, and Regioselective Iridium-Catalyzed Asymmetric Allylic Alkylation of Acyclic β-Ketoesters
The first regio-, diastereo-, and enantioselective allylic alkylation of acyclic β-ketoesters to form vicinal tertiary and all-carbon quaternary stereocenters is reported. Critical to the successful development of this method was the employment of iridium catalysis in concert with N-aryl-phosphoramidite ligands. Broad functional group tolerance is observed at the keto-, ester-, and α-positions of the nucleophile. Various transformations demonstrating the utility of this method for rapidly accessing complex enantioenriched compounds are reported.
Additional Information© 2013 American Chemical Society. Received: September 20, 2013; Published: October 28, 2013. The authors wish to thank NIH-NIGMS (R01GM080269), Amgen, the Gordon and Betty Moore Foundation, the Caltech Center for Catalysis and Chemical Synthesis, and Caltech for financial support. Shanghai Institute of Organic Chemistry (SIOC) is thanked for a postdoctoral fellowship to W.-B.L. Lawrence Henling is acknowledged for X-ray crystallographic structural determination. We thank the reviewers for the valuable suggestions about the Hammett correlation and Brown σ+ constants.
Accepted Version - nihms537549.pdf
Supplemental Material - ja4097829_si_001.cif
Supplemental Material - ja4097829_si_002.pdf