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COMMUNICATION
ChemComm
be trapped by the pendant amine group to arrive, after the
loss of H+, at a putative intermediate
. Another iron-mediated
SET oxidation with DDQ converts to radical 4a. This cyclic
radical then undergoes further oxidation to arrive at
In summary, we have developed a novel protocol for the
preparation of N-heterocycles via intramolecular sp3 C-H
amination under Fe-assisted SET oxidation with DDQ. This
methodology offers a novel approach to intramolecular C-H
aminations in route to N-heterocyclic compounds.
DOI: 10.1039/C6CC03106D
3
J. Org. Chem. 2015, 4, 573. (c) Huang, P.-C.; Gandeepan, P.;
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For selected examples of manganese-mediated C-H
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5
.
10 For selected examples of iron-mediated C-H aminations: (a)
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11 For reviews/examples of oxidative and radical C-H
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ACKNOWLEDGMENT
The authors are grateful to Michelle Ly for insightful discussions
and aid in preparing starting materials, and to David Dan for
the preparation of substrate 5r. I. A. is grateful to the National
Science Foundation (CHE-1465142) for support of this research.
12 For selected examples of radical stabilization by donor
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15 In the case of 1r, poor conversion was observed with a
complex mixture of products and no detectable amount of
5r. In the case of 1q, poor conversion was observed with a
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1H/13CNMR are supplied.
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