Organic Letters
Letter
and 1j to terminal olefin 3i through tertiary centers also occurred
in good yields. Acyclic olefins also underwent isomerization
through branched alkyl chains. For example, the long-range
isomerization of acyclic 1,2-disubstituted olefin 1k to 1,1-
disubstituted olefin 3k proceeded in good yield. In addition, the
isomerization tolerates steric hindrance at the starting alkene.
Conversion of the hindered, trisubstituted olefin 1l, which bears
a tert-butyl substituent α to the double bond, to olefin 3l
occurred in good yield.
Author Contributions
†S.H. and T.W.B. contributed equally.
Funding
This work was supported by the Director, Office of Science, U.S.
Department of Energy, under Contract No. DE-AC02-
05CH1123.
Notes
The authors declare no competing financial interest.
Finally, this type of contra-thermodynamic isomerization can
be conducted on large scales. The isomerization of olefin 1h to
olefin 3h occurred in 71% isolated yield on a gram scale (Scheme
ACKNOWLEDGMENTS
■
Steven Hanna gratefully acknowledges Chevron for a predoc-
toral fellowship, and Trevor W. Butcher gratefully acknowledges
the National Science Foundation for a predoctoral fellowship.
5
).
Scheme 5. Contra-thermodynamic Isomerization on a Gram
a
Scale
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While other hydrofunctionalizations could be envisioned to be
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Synthetic procedures and analytical data from H NMR
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and NMR spectroscopy (PDF)
AUTHOR INFORMATION
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*
ORCID
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Org. Lett. XXXX, XXX, XXX−XXX