Organic Letters
Letter
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Figure 1. Synthesis of five- and seven-membered γ,γ-disubstituted
cycloalkenones.
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In summary, we have developed a palladium-catalyzed α-
arylation protocol for the synthesis of vinylogous esters bearing
a quaternary carbon center, which can readily be converted to
γ-alkyl-γ-aryl-substituted cyclohexenones. The method is
modular, and the scope of aryl bromides is particularly broad,
with a range of functional groups and heterocycles being
tolerated. Efforts are underway to extend this method to the
synthesis of more complex molecules.
ASSOCIATED CONTENT
* Supporting Information
■
S
The Supporting Information is available free of charge on the
Detailed experimental procedures and characterization
X-ray crystallographic data for 2aa (CIF)
(12) A list of unsuccessful aryl bromides is provided in the
(13) Review of alkenylation of enolates: Ankner, T.; Cosner, C. C.;
Helquist, P. Chem. - Eur. J. 2013, 19, 1858.
(14) The γ-arylated byproduct was isolated in 32% yield.
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(16) Majetich, G.; Liu, S.; Fang, J.; Siesel, D.; Zhang, Y. J. Org. Chem.
1997, 62, 6928.
AUTHOR INFORMATION
■
Corresponding Author
ORCID
Author Contributions
†T.J. and F.P. contributed equally.
Notes
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
■
This work was supported financially by the Natural Sciences
and Engineering Research Council (NSERC), the University of
Toronto, and Alphora Research, Inc. T.J. thanks NSERC for a
graduate scholarship. F.P. thanks Ludwig-Maximilians-Uni-
versitat Munchen for a research scholarship (Prosa LMU)
̈
̈
financed by the Deutscher Akademischer Austauschdienst
(DAAD) and the State of Bavaria. Mr. Egor Larin (University
of Toronto) is thanked for experimental assistance. Dr. Alan
Lough (University of Toronto) is thanked for obtaining an X-
ray crystal structure of 2aa.
REFERENCES
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Org. Lett. XXXX, XXX, XXX−XXX