Organic Letters
Letter
and further efforts to improve the enantio- and diastereose-
lectivity of this reaction are underway.
Scheme 2. Substrate Scope for the Reaction of Allylic
Phosphates with Substituted gem-Diborylalkanes
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ASSOCIATED CONTENT
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* Supporting Information
The Supporting Information is available free of charge on the
Detailed experimental procedures and spectra data for all
AUTHOR INFORMATION
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Corresponding Authors
Notes
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Reactions were carried out under the conditions shown, all yields
The authors declare no competing financial interest.
were isolated yields, and the ratios of SN2′/SN2 were determined by
1H NMR analysis of the reaction mixture.
ACKNOWLEDGMENTS
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Scheme 3. Reaction of Allylic Epoxide with Substituted gem-
Diborylalkanes
We thank the 973 Program (2012CB215306), NSFC
(21302178, 21325208, 21572212, 21361140372),
IPDFHCPST (2014FXCX006), SRFDP (20133402120034),
CAS (KFJ-EW-STS-051, YIPA-2015371), FRFCU, and
PCSIRT.
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REFERENCES
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a
Reactions were carried out under the conditions shown, all yields are
1
isolated yields, and the ratios of SN2′/SN2 were determined by H
NMR analysis of the reaction mixture.
We found that the ee value can be governed when
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pinacol, 40% ee, X = pinanediol, 64% ee) (Scheme 4; for
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Scheme 4. Asymmetric Selectivity of the Reaction of Allylic
a
Phosphates with Diborylmethane
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a
Reactions were carried out under the conditions shown, all yields are
isolated yields, and the ee value were determined by HPLC analysis.
In summary, we have reported a copper-catalyzed SN2′-
selective allylic alkylation reaction of allylic electrophiles with
substituted gem-diborylalkanes.16 A variety of synthetically
important functional groups can be compatible under these
conditions. The asymmetric version of this reaction was initially
researched with chiral N-heterocyclic carbene (NHC) ligands,
(3) Hall, D. G. In Boronic Acids; Wiley−VCH, 2006; p 1.
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Org. Lett. XXXX, XXX, XXX−XXX