Journal of the American Chemical Society
Communication
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(6) Procter, D. J.; Flowers, R. A., II; Skrydstrup, T. Organic Synthesis
using Samarium Diiodide: A Practical Guide; RSC Publishing:
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(7) Recent reviews on SmI2: (a) Molander, G. A.; Harris, C. R. Chem.
Rev. 1996, 96, 307. (b) Krief, A.; Laval, A. M. Chem. Rev. 1999, 99,
745. (c) Kagan, H. B. Tetrahedron 2003, 59, 10351. (d) Nicolaou, K.
C.; Ellery, S. P.; Chen, J. S. Angew. Chem., Int. Ed. 2009, 48, 7140.
(e) Szostak, M.; Spain, M.; Procter, D. J. Chem. Soc. Rev. 2013,
DOI: 10.1039/C3CS60223K.
H2O. Remarkably, the reagent system is fully chemoselective
for the reduction of lactones over esters and has been exploited
in reductive carbon−carbon bond formation to rapidly build-up
molecular complexity. Importantly, the current study is one of
the few examples of substrate-directable reactions proceeding
via sequential one-electron mechanisms. We believe that these
findings will have an important impact for the activation of inert
functional groups via open-shell reaction pathways. Application
of this strategy to other substrate-directable electron transfer
reactions is underway in our laboratory and will be described
shortly.
ASSOCIATED CONTENT
* Supporting Information
■
(8) For a seminal mechanistic study on the β-directing effect, see:
Prasad, E.; Flowers, R. A., II. J. Am. Chem. Soc. 2002, 124, 6357.
(9) Reviews: (a) Dahlen, A.; Hilmersson, G. Eur. J. Inorg. Chem.
́
2004, 3393. (b) Szostak, M.; Spain, M.; Parmar, D.; Procter, D. J.
Chem. Commun. 2012, 48, 330.
S
Experimental procedures, compound characterization data, and
details of rate studies. This material is available free of charge
(10) Duffy, L. A.; Matsubara, H.; Procter, D. J. J. Am. Chem. Soc.
2008, 130, 1136.
AUTHOR INFORMATION
Corresponding Authors
■
(11) For selected studies on SmI2−H2O, see: (a) Parmar, D.; Duffy,
L. A.; Sadasivam, D. V.; Matsubara, H.; Bradley, P. A.; Flowers, R. A.,
II; Procter, D. J. J. Am. Chem. Soc. 2009, 131, 15467. (b) Parmar, D.;
Price, K.; Spain, M.; Matsubara, H.; Bradley, P. A.; Procter, D. J. J. Am.
Chem. Soc. 2011, 133, 2418. (c) Parmar, D.; Matsubara, H.; Price, K.;
Spain, M.; Procter, D. J. J. Am. Chem. Soc. 2012, 134, 12751.
(d) Guazzelli, G.; De Grazia, S.; Collins, K. D.; Matsubara, H.; Spain,
M.; Procter, D. J. J. Am. Chem. Soc. 2009, 131, 7214. (e) Szostak, M.;
Spain, M.; Procter, D. J. Chem. Commun. 2011, 47, 10254. For a
related study on TmI2−H2O, see: (f) Szostak, M.; Spain, M.; Procter,
D. J. Angew. Chem., Int. Ed. 2013, 52, 7237.
(12) Selected recent mechanistic studies on SmI2 reductants:
(a) Miller, R. S.; Sealy, J. M.; Shabangi, M.; Kuhlman, M. L.; Fuchs,
J. R.; Flowers, R. A., II. J. Am. Chem. Soc. 2000, 122, 7718. (b) Prasad,
E.; Flowers, R. A., II. J. Am. Chem. Soc. 2002, 124, 6895. (c) Sadasivam,
D. V.; Antharjanam, P. K. S.; Prasad, E.; Flowers, R. A., II. J. Am. Chem.
Soc. 2008, 130, 7228. (d) Choquette, K. A.; Sadasivam, D. V.; Flowers,
R. A., II. J. Am. Chem. Soc. 2010, 132, 17396.
(13) (a) Chopade, P. R.; Prasad, E.; Flowers, R. A., II. J. Am. Chem.
Soc. 2004, 126, 44. (b) Prasad, E.; Flowers, R. A., II. J. Am. Chem. Soc.
2005, 127, 18093. (c) Amiel-Levy, M.; Hoz, S. J. Am. Chem. Soc. 2009,
131, 8280.
(14) (a) Newcomb, M. Tetrahedron 1993, 49, 1151. (b) Hasegawa,
E.; Curran, D. P. Tetrahedron Lett. 1993, 34, 1717. (c) Curran, D. P.;
Fevig, T. L.; Jasperse, C. P.; Totleben, J. Synlett 1992, 943.
(d) Stevenson, J. P.; Jackson, W. F.; Tanko, J. M. J. Am. Chem. Soc.
2002, 124, 4271.
Notes
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
■
We acknowledge the EPSRC and GSK for financial support.
R.A.F thanks the National Science Foundation (CHE 0844946
and 1266333) for the work at Lehigh University.
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