Organic Letters
Letter
molecular HAT reactions could take place (Scheme 4). As a
result, the reaction continues toward the multiple (triple)
iodination of the methyl group, leading to the formation of 14c
after cyclization.
Furthermore, we observed that 14(I2) could be efficiently
transformed into 14c employing the GP3Na2CO3 (Table 3, entry
AUTHOR INFORMATION
Corresponding Authors
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Notes
The authors declare no competing financial interest.
Table 3. Monitored Experiments with 14(I2) by 1H NMR
ACKNOWLEDGMENTS
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This work was supported by the research programs ref
CTQ2007-67492/BQU of the Ministerio de Educacion
́
y
Ciencia, Spain, and Gobierno de Canarias ref ProID20100088.
The COST Action CM1201 “Biomimetic Radical Chemistry” is
also acknowledged. R.M. and D.R.-S. thank the Program JAE-
C.S.I.C. for fellowships. We thank Dr. A. G. Santana (IPNA-
CSIC) for helpful discussions.
REFERENCES
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a
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1) via cyclization of the pseudostable intermediate 14(I3) (entry
2). Likewise, we propose that an intramolecular redox activation
is determinant in the formation of lactam 14c (Scheme S12,
Supporting Information). 14(I2) could also be almost
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deiodination mechanism in absence of light. This cyclization is
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14(I3) employing GP3Na2CO3 under irradiation (compare entry 2
and entry 4, Scheme S12). Moreover, we elucidated that neither
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conditions (Scheme S16). Thus, we defined that the formation of
pyrrolidines Na involves a single hydrogen atom transfer process
(SHAT), while the formation of 2-pyrrolidinones requires a
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In summary, the herein described tunable reactivity of N-iodo
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Consequently, we present a new methodology to synthesize
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(16) The results obtained when other interesting selected conditions
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ASSOCIATED CONTENT
* Supporting Information
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S
Experimental procedures, full characterization of products, DFT
calculations, NMR-monitored experiments, additional schemes,
and copies of NMR spectra. The Supporting Information is
D
Org. Lett. XXXX, XXX, XXX−XXX