Lamp versus laser photolysis of 1,3-dichloro-1,3-diphenylpropane in cyclohexane. Direct observation of 1,3-diphenylpropenyl radical

Tetrahedron Letters

Volumn 37, Issue 28, 1996, Pages 4923-4926

  Pérez Prieto, Julia ^a   Miranda, Miguel Angel ^b   Font Sanchis, Enrique ^a   Kónya, Klára ^c   Scaiano, J C ^c  

^a UNIVERSITY OF VALENCIA   (Spain)

^b UNIVERSITAT POLITÈCNICA DE VALÈNCIA   (Spain)

^c UNIVERSITY OF OTTAWA   (Canada)

Author keywords

[No Author keywords available]

Indexed keywords

ALLYL COMPOUND; CYCLOHEXANE; CYCLOPROPANE DERIVATIVE; PROPANE; RADICAL;

ABSORPTION SPECTROSCOPY; ARTICLE; CIS TRANS ISOMERISM; IRRADIATION; LASER; PHOTOCHEMISTRY; PHOTOLYSIS; PHOTON;

EID: 1542432682     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/0040-4039(96)00987-2     Document Type: Article

References (22)

1. (1) Banks, J. T.; García, H.; Miranda, M. A.; Pérez-Prieto, J.; Scaiano, J. C. J. Am. Chem. Soc. 1995, 117, 5049.
2. (2) Ouchi, A.; Yabe, A. Tetrahedron Lett. 1992, 33, 5359.
3. (3) Ouchi, A.; Yabe, A.; Adam, W. Tetrahedron Lett. 1994, 35, 6309.
4. (4) Pérez-Prieto, J.; Miranda, M. A.; Garcia, H.; Kónya, K.; Scaiano, J. C. J. Org. Chem. in press.
5. (5) Adam, W.; Ouchi, A. Tetrahedron Lett. 1992, 33, 1875.
6. (6) Boche, G.; Schneider, D. R. Angew. Chem. Int. Ed. Engl. 1977, 16, 869.
7. (7) Beilstein Handbuch der Organische Chemie H, 5, 71.
8. (8) Bunce, N. J.; Ingold, K. U.; Landers, J. P.; Lusztyk, J.; Scaiano, J. C. J. Am. Chem. Soc. 1985, 107, 5464.
9. 13C-NMR: 144.2(s), 142.7 (s), 128.6 (d), 128.3 (d), 128.1(d), 128.0 (d), 125.8 (d), 125.5 (d), 51.7 (d), 43.34 (d), 34.47 (t), 34.0 (t), 31.3 (t), 31.0 (t), 26.5 (t). Anal. Calc. C: 90.65%, H: 9.34%; Found C: 90.67%, H: 9.38%, mass. spec. (m/z) 278 (13), 196 (13), 91 (100).
10. (10) Compounds 1, 2 and 7 are mixtures of two stereoisomers.
11. (11) The laser system uses Lumonics EX-510 and EX-530 for excitation wavelengths of 248 and 308 nm, Surelite lasers from Continuum for the Nd-YAG wavelengths of 266, 355 and 532 nm and a Molectron UV-24 nitrogen laser for 337 nm. All pulse durations are <10 ns and typical pulse energies between 5 and 50 mJ. The signals from the monochromator/photomultiplier system were initially captured by a Tektronix 2440 digitiger and transfered to a PowerMacintosh computer that controlled the experiment with software developed in the LabVIEW 3.1.1 environment from National Instruments. Other aspects of the system are similar to those described earlier: Scaiano, J. C. J. Am. Chem. Soc. 1980, 102, 7747; Scaiano, J. C.; Tanner, M.; Weir, D. J. Am. Chem. Soc. 1985, 107, 4396.
12. (11) The laser system uses Lumonics EX-510 and EX-530 for excitation wavelengths of 248 and 308 nm, Surelite lasers from Continuum for the Nd-YAG wavelengths of 266, 355 and 532 nm and a Molectron UV-24 nitrogen laser for 337 nm. All pulse durations are <10 ns and typical pulse energies between 5 and 50 mJ. The signals from the monochromator/photomultiplier system were initially captured by a Tektronix 2440 digitiger and transfered to a PowerMacintosh computer that controlled the experiment with software developed in the LabVIEW 3.1.1 environment from National Instruments. Other aspects of the system are similar to those described earlier: Scaiano, J. C. J. Am. Chem. Soc. 1980, 102, 7747; Scaiano, J. C.; Tanner, M.; Weir, D. J. Am. Chem. Soc. 1985, 107, 4396.
13. (12) Benzylic radicals normally show absorptions in this spectral region: Chatgilialoglu, C. In Handbook of Organic Photochemistry; J. C. Scaiano, Ed.; CRC Press: Boca Raton, Florida, 1989; Vol. II; p 3.
14. (13) Hayashi, T.; Yamamoto, A.; Ito, Y.; Nishioka, E.; Miura, H.; Yanagi, K. J. Am. Chem. Soc. 1989, 111, 6301.
15. (14) Carsky, P.; Zahradnik, R. J. J. Phys. Chem. 1970, 74, 1249.
16. (15) Paul, H.; Small, R. D., Jr.; Scaiano, J. C. J. Am. Chem. Soc. 1978, 100, 4520.
17. (16) Oxygen leads to a complex mixture of products, characteristic of radical processes. 1,3-Diphenyl-propene oxide, the two isomeric chalcones and some dibenzyl ketone are among the products. Attempts to detect singlet oxygen luminescence were unsuccessful, a result that is consistent with the involvement of radicals rather than long lived excited states.
18. (17) Mizuno, K.; Ichinose, N.; Otsuji, Y.; Caldwell, R. A. J. Am. Chem. Soc. 1985, 107, 5797.
19. (18) Zimmt, M. B.; Doubleday, C., Jr.; Turro, N. J. Chem. Phys. Lett. 1987, 134, 549.
20. (19) This technique allows for semipreparative experiments under conditions of high intensity pulsed laser irradiation. For further details see: Banks, J. T.; Scaiano, J. C. J. Am. Chem. Soc. 1993, 115, 6409.
21. (20) For other examples of two-photon processes, see: Scaiano, J. C.; Johnston, L. J.; McGimpsey, W. G.; Weir, D. Acc. Chem. Res. 1988, 21, 22 and references therein.
22. (21) Financial support by the Natural Science and Engineering Council of Canada through an operating Grant (JCS) and Spanish DGICYT (MAM, Project no. PB94-0539; JP-P, Project no PR-95-289) are gratefully acknowledged. JCS is the recipient of a Killam Fellowship awarded by the Canada Council.