ꢀ
E. Campos-Gomez et al. / Tetrahedron 68 (2012) 4292e4295
4295
4.3.7. Naphthol[1,2-b]thiophene23 (14). Obtained from irradiation
of 13, through Pyrex, for 16 h.
Universidad de La Rioja (API11/20). H.F.G. thanks the Comunidad
ꢀ
Autonoma de La Rioja for his fellowship.
4.3.8. Benzo[f]isoquinoline24 (16). Obtained from irradiation of 15,
through Pyrex, for 16 h.
References and notes
1. CRC handbook of organic photochemistry and photobiology; Horspool, W.,
Lenci, F., Eds. ; CRC: Boca Raton, USA, 2004; vols. 1 and 2.
4.3.9. 2-(2-(phenylselanyl)vinyl)biphenyl (17). Obtained from irra-
diation of 1 with a 125 W Hg lamp, through Vycor, for 6 h in the
presence of 5 equiv of PhSeSePh. Exact mass ESI(þ) (C20H16SeþAg):
calculated 442.9468, measured 442.9463.
2. Selected reviews on the chemistry of radicals: (a) Curran, D. P.; Porter, N. A.;
Giese, B. Stereochemistry of Radical Reactions; VCH: Weinheim, Germany, 1996;
(b) Radicals in Organic Synthesis; Renaud, P., Sibi, M. P., Eds.; Wiley-VCH:
Weinheim, Germany, 2001; (c) Tumanskii, B.; Kalina, O. Radical Reactions of
Fullerenes and Their Derivatives; Kluwer Academic: Dordrecht, The Netherlands,
2001; (d) Zard, S. Z. Radical Reactions in Organic Synthesis; Oxford University:
Oxford, U.K, 2003; (e) Togo, H. Advanced Free Radical Reactions for Organic
Synthesis; Elsevier: Oxford, U.K, 2004; (f) Perchyonok, T. V. Radical Reactions in
Aqueous Media; The Royal Society of Chemistry: Cambridge, U.K, 2010.
3. (a) Alonso, R.; Campos, P. J.; García, B.; Rodríguez, M. A. Org. Lett. 2006, 8, 3521;
(b) Alonso, R.; Campos, P. J.; Rodríguez, M. A.; Sampedro, D. J. Org. Chem. 2008,
73, 2234; (c) Alonso, R.; Caballero, A.; Campos, P. J.; Rodríguez, M. A. Tetrahe-
dron 2010, 66, 8828.
4.3.10. (Styryl)(phenyl)selenide25 (18). Obtained from irradiation of
b
-iodostyrene with a 125 W Hg lamp, through Vycor, for 6 h in the
presence of 5 equiv of PhSeSePh. Exact mass ESI(þ) (C14H12SeþAg):
calculated 366.9155, measured 366.9150.
4.4. Experimental procedure for irradiation of 1 in the
presence of different triplet quenchers
4. Sha, C.-K.; Santhosh, K. C.; Tseng, C.-T.; Lin, C.-T. Chem. Commun. 1998, 397.
5. Curran, D. P.; Chang, C.-T. J. Org. Chem. 1989, 54, 3140.
Three 1.02ꢁ10ꢂ2 M solutions of iodoalkene 1 in acetonitrile
were contained in three 20 ml quartz tubes. One tube was satu-
rated with oxygen. About 10 equiv of piperylene were added to the
second tube. The last tube was kept deoxygenated and triplet
quencher free. The irradiation was performed for 6 h with a 125 W
medium pressure-mercury lamp in a merry-go-round reactor
through Vycor, which removes radiation wavelength under
250 nm. The solvent was then removed from the reaction mix-
tures with a rotary evaporator and the amounts of 1 and 2 were
quantified by 1H RMN using a solution of 1,3,5-trimethoxybenzene
as an internal standard.
6. (a) Clyne, M. A.; Aldabbagh, F. Org. Biomol. Chem. 2006, 4, 268; (b) Linsenmeier,
€
A. M.; Williams, C. M.; Brase, S. J. Org. Chem. 2011, 76, 9127.
7. Curran, D. P.; Guthrie, D. B.; Geib, S. J. J. Am. Chem. Soc. 2008, 130, 8437.
~ꢀ
8. (a) Campos, P. J.; Tan, C.-Q.; Rodríguez, M. A.; Anon, E. J. Org. Chem. 1996, 61,
7195; (b) Campos, P. J.; Sampedro, D.; Rodríguez, M. A. Organometallics 2000,
19, 3082; (c) Campos, P. J.; Sampedro, D.; Rodríguez, M. A. Organometallics
2002, 21, 4076; (d) Campos, P. J.; Sampedro, D.; Rodríguez, M. A. J. Org. Chem.
2003, 68, 4674; (e) Sampedro, D.; Caro, M.; Rodríguez, M. A.; Campos, P. J. J. Org.
Chem. 2005, 70, 6705; (f) Campos, P. J.; Soldevilla, A.; Sampedro, D.; Rodríguez,
M. A.; Olivucci, M. J. Am. Chem. Soc. 2005, 127, 441; (g) Soldevilla, A.; Sampedro,
D.; Campos, P. J.; Rodríguez, M. A. J. Org. Chem. 2005, 70, 6976.
9. (a) Barluenga, J.; Rodríguez, M. A.; Campos, P. J.; Asensio, G. J. Am. Chem. Soc.
1988, 110, 5567; (b) Barluenga, J.; Rodríguez, M. A.; Campos, P. J. J. Org. Chem.
1990, 55, 3104; (c) Campos, P. J.; Tan, C.-Q.; Rodríguez, M. A. Tetrahedron Lett.
1995, 36, 5257; (d) Campos, P. J.; Arranz, J.; Rodríguez, M. A. Tetrahedron Lett.
1997, 38, 8397; (e) Campos, P. J.; García, B.; Rodríguez, M. A. Tetrahedron Lett.
2000, 41, 979; (f) Campos, P. J.; García, B.; Rodríguez, M. A. Tetrahedron Lett.
4.5. Experimental procedure for quantum yield
determination of 1
ꢀ
ꢀ
2002, 43, 6111; (g) Barluenga, J.; Campos-Gomez, E.; Rodríguez, D.; Gonzalez-
ꢀ
Bobes, F.; Gonzalez, J. M. Angew. Chem., Int. Ed. 2005, 117, 6001.
10. Prepared according to Cullen, K. E.; Sharp, J. T. J. Chem. Soc., Perkin Trans. 1 1993,
2961.
11. Stork, G.; Zhao, K. Tetrahedron Lett. 1989, 30, 2173.
12. The product 10 absorbs more intensely than 9. Irradiation of 9 for 24 hours led
to a 10:9 ratio of 1:1.37, as determined by 1H NMR of the crude reaction.
13. Kuhn, H. J.; Braslavsky, S. E.; Schmidt, R. Pure Appl. Chem. 2004, 76, 2105.
14. (a) Poindexter, G. S.; Kropp, P. J. J. Am. Chem. Soc. 1974, 96, 7142; (b) See Ref. 1;
Kropp, P.J.; Vol. 1, Chapter 1, p 1e1.
The quantum yield of the efficiency of appearance of 2 was
determined using a solution of trans-azobenzene actinometer,
which absorbance at 358 nm was about 1. The irradiation was
carried out at 280 nm using a 500 W Hg(Xe) lamp and an Oriel
Cornestone 130 1/8m monochromator. trans-Azobenzene solution
was irradiated for 15 min and the absorbance at 358 nm was
measured (except during irradiation, only radiationꢄ500 nm was
admitted to the sample). Then, a solution 1.6ꢁ10ꢂ4 M of 1 in de-
oxygenated acetonitrile was irradiated at 280 nm for 4 h, the sol-
vent was removed from the reaction mixture with a rotary
evaporator and the amount of 2 were quantified by 1H RMN using
a solution of 1,3,5-trimethoxybenzene as an internal standard. The
quantum yield value was determined by the literature method.13
Supplementary data associated with this article can be found, in
15. Parsons, A. F. An Introduction to Free Radical Chemistry; Oxford: Blackwell, 2000;
p 68.
16. Although the pH in non-aqueous solvents and water are far from being com-
pared, the retrieved value [pH (acetonitrile)¼2.1] is clearly acid. See, for ex-
ample, Laitinen, H. A.; Harris, W. E. Chemical Analysis. An Advanced Text and
Reference, 2nd ed.; McGraw-Hill: New York, USA, 1975, Chapter 4, p 56.
17. Cullen, K. E.; Sharp, J. T. J. Chem. Soc., Perkin Trans. 1 1993, 2961.
18. Jackson, T. J.; Herndon, J. W. Tetrahedron 2001, 57, 3859.
ꢀ
19. Bonnet, B.; Gallic, Y. L.; Ple, G.; Duhamel, L. Synthesis 1993, 1071.
20. Barluenga, J.; Rodríguez, M. A.; Campos, P. J.; Asensio, G. Tetrahedron Lett. 1986,
28, 3303.
21. Bernardon, J.-M.; Nedoncelle, P. Eur. Pat. Appl. 1998, EP 879814 A1 19981125.
22. Kim, N.; Yi, K. Y.; Yoo, S.-E.; Kim, G.; Park, S. K. J. Photochem. Photobiol., A: Chem.
2005, 170, 169.
€
23. Mamane, V.; Louerat, F.; Iehl, J.; Abboud, M.; Fort, Y. Tetrahedron 2008, 64,
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€
24. Mamane, V.; Hannen, P.; Furstner, A. Chem.dEur. J. 2004, 10, 4556.
This work was partially supported by the Ministerio de Ciencia e
~
25. Gonc¸ alves, L. C.; Fiss, G. F.; Perin, G.; Alves, D.; Jacob, R. G.; Lenardao, E. J.
ꢀ
Innovacion of Spain (CTQ2007-64197 and CTQ2011-24800) and
Tetrahedron Lett. 2010, 51, 6772.