Organic Letters
Letter
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Scheme 4. Proposed Mechanism
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(17) In ref 16, a single (Ir-catalyzed) example of an acetate leaving
group as well as the cleavage of an α-formyl benzyl ether are reported,
the latter of which, however, might be subject to a different mechanism.
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demonstrate the convenient application of these versatile α-aryl
ketone building blocks for the synthesis of arylbenzofurans.
(19) Chenneberg, L.; Baralle, A.; Daniel, M.; Fensterbank, L.;
Goddard, J.-P.; Ollivier, C. Adv. Synth. Catal. 2014, 356, 2756.
(20) Rackl, D.; Kais, V.; Kreitmeier, P.; Reiser, O. Beilstein J. Org. Chem.
2014, 10, 2157.
ASSOCIATED CONTENT
* Supporting Information
The Supporting Information is available free of charge on the
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(21) (a) Kim, H.; Lee, C. Angew. Chem., Int. Ed. 2012, 51, 12303.
(b) Nguyen, J. D.; D’Amato, E. M.; Narayanam, J. M. R.; Stephenson, C.
R. J. Nat. Chem. 2012, 4, 854.
Experimental procedures and spectral data (PDF)
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ova, Z.; Smejkal, K.; Dall
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(22) (a) Zelova,
Acqua, S.; Babula, P.; Cvack
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H.; Hanak
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ova,
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Z.; Cermak
k, J. J. Nat. Prod. 2014, 77, 1297.
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a, J.; Hose
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AUTHOR INFORMATION
Corresponding Author
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(b) Yang, Y.; Gong, T.; Liu, C.; Chen, R.-Y. Chem. Pharm. Bull. 2010, 58,
257. (c) Keay, B. A.; Dibble, P. W. Furans and their Benzo Derivatives:
Applications. Comprehensive Heterocyclic Chemistry III; Elsevier: Oxford,
2008; p 571.
Notes
(23) (a) Neumann, M.; Fuldner, S.; Konig, B.; Zeitler, K. Angew. Chem.,
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The authors declare no competing financial interest.
Int. Ed. 2011, 50, 951. (b) Hari, D. P.; Konig, B. Chem. Commun. 2014,
50, 6688.
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ACKNOWLEDGMENTS
(24) A related notice was also reported using UV-light irradiation, but
according to λHantzsch ester 300−420 nm excitation with blue light is
amenable.18b,25 (a) Zhang, J.; Jin, M.-Z.; Zhang, W.; Yang, L.; Liu, Z.-L.
Tetrahedron Lett. 2002, 43, 9687. (b) Zhang, H.-H.; Liu, Q.; Feng, K.;
Chen, B.; Tung, C.-H.; Wu, L.-Z. Langmuir 2012, 28, 8224.
(25) With green light irradiation only traces of deoxygenated product
were observed. Combination of blue LED light with a NaNO2 solution
UV-cutoff filter (i. e., λ > 400 nm) reproduced the results of entry 10,
Table 1.
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This work was generously supported by the DFG (GRK 1626
“Chemical Photocatalysis”) and the EU (IEF Marie-Curie
Fellowship for C.P.).
REFERENCES
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