Multi-step photolysis of benzenetetracarboxylic dianhydrides in low-temperature argon matrices: exploration of reactive intermediates containing benzdiynes produced stepwise during photochemical reactions

Abstract

Photolyses of 1,2;4,5- and 1,2;3,4-benzenetetracarboxylic dianhydrides (3a and 3b), which would be precursors of 1,4- and 1,3-benzdiyne (2a and 2b), were studied by a matrix isolation technique and a selective irradiation technique using three kinds of excimer lasers in order to directly observe intermediates produced stepwise. The photolyzed products in the matrix were characterized by FT-IR and UV–vis spectroscopies. As a result, sequential decarboxylation and decarbonylation from one anhydride moiety of 3a and 3b produced corresponding benzocyclopropenone and benzyne intermediates in the initial stage. In both the photolyses, further decomposition proceeded to form 1,3,5-hexatriyne (4) as a final product. Although neither 2a nor 2b was observed directly, it seems that the benzdiynes including another isomer, 1,2,3,5-tetradehydrobenzene (2c), participated as precursors to acyclic C₄H–Câ–·C–H biradical 13 and/or carbene 14, which were formed in the reaction from benzdiyne to 4. Additionally, as a result of CCSD(T)/6-31G**//CASSCF(4,4)/6-31G** level calculations for 2a, 2b and 2c, it is clear that the energy of 2c was comparable to those of 2a and 2b, which supports the formation of 13 from 2a/2b and of 14 from 2c after isomerization of 2a→2c and 2b→2c.

References

1. (a) O. L. Chapman, K. Mattes, C. L. McIntosh, J. Pacansky, G. V. Calder and G. Orr, J. Am. Chem. Soc., 1973, 95, 6134; (b) O. L. Chapman, C.-C. Chang, J. Kolc, N. R. Rosenquist and H. Tomioka, J. Am. Chem. Soc., 1975, 97, 6586; (c) I. R. Dunkin and J. G. MacDonald, J. Chem. Soc., Chem. Commun., 1979, 772; (d) H.-H. Nam and G. E. Leroi, J. Mol. Struct., 1987, 157, 301; (e) R. F. C. Brown, N. R. Browne, K. J. Coulston, L. B. Danen, F. W. Eastwood, M. J. Irvine and A. D. E. Pullin, Tetrahedron Lett., 1986, 27, 1075; (f) C. Wentrup, R. Blanch, H. Briehl and G. Gross, J. Am. Chem. Soc., 1988, 40, 1874; (g) J. G. G. Simon, N. Münzel and A. Schweig, Chem. Phys. Lett., 1990, 170, 187; (h) J. G. Radziszewski, J. B. A. Hess and R. Zahradnik, J. Am. Chem. Soc., 1992, 44, 52; (i) N. Münzel and A. Schweig, Chem. Phys. Lett., 1988, 147, 192; (j) A. M. Orendt, J. C. Facelli, J. G. Radziszewski, W. J. Horton, D. M. Grant and J. Michl, J. Am. Chem. Soc., 1996, 48, 846.
2. (a) R. Zahradnik, P. Hobza, R. Burcl, B. A. Hess, Jr. and J. G. Radziszewski, J. Mol. Struct. (THEOCHEM), 1994, 313, 335; (b) L. Radom, R. H. Nobes, D. J. Underwood and W.-K. Li, Pure. Appl. Chem., 1986, 58, 75.
3. M. Moriyama, T. Ohana and A. Yabe, J. Am. Chem. Soc., 1997, 49, 10229.
4. (a) M. Moriyama, T. Ohana and A. Yabe, Chem. Lett., 1995, 557; (b) M. Moriyama and A. Yabe, Chem. Lett., 1998, 337.
5. Gaussian 94 (Revision E.2), M. J. Frisch, G. W. Trucks, H. B. Schlegel, P. M. W. Gill, B. G. Johnson, M. A. Robb, J. R. Cheeseman, T. Keith, G. A. Petersson, J. A. Montgomery, K. Raghavachari, M. A. Al-Laham, V. G. Zakrzewski, J. V. Ortiz, J. B. Foresman, J. Cioslowski, B. B. Stefanov, A. Nanayakkara, M. Challacombe, C. Y. Peng, P. Y. Ayala, W. Chen, M. W. Wong, J. L. Andres, E. S. Replogle, R. Gomperts, R. L. Martin, D. J. Fox, J. S. Binkley, D. J. Defrees, J. Baker, J. P. Stewart, M. Head-Gordon, C. Gonzalez and J. A. Pople, Gaussian, Inc., Pittsburgh PA, 1995.
6. B. O. Roos, Adv. Chem. Phys., 1987, 69, 399.
7. P. G. Wenthold, J. A. Paulino and R. R. Squires, J. Am. Chem. Soc., 1991, 43, 7414.
8. (a) W. R. Maxwell and J. R. Partington, Trans. Faraday Soc., 1936, 32, 775; (b) M. Takahashi, Bull. Chem. Soc. Jpn., 1968, 41, 265.
9. D. McNaughton and D. N. Bruget, J. Mol. Spectrosc., 1991, 150, 620.
10. (a) R. Breslow and G. Ryan, J. Am. Chem. Soc., 1967, 89, 3073; (b) O. L. Chapman, J. Gano, P. R. West, M. Regitz and G. Maas, J. Am. Chem. Soc., 1981, 113, 7033; (c) J. G. G. Simon, A. Schweig, Y. Xie and H. F. Schaefer III, Chem. Phys. Lett., 1992, 200, 631.
11. Mass spectra of 6a, 9a and 10a. (a)6a: m/z 206(M⁺), 175(M⁺– OCH₃), 162(M⁺– CO₂), 147(M⁺– COOCH₃), 103(M⁺– CO₂– COOCH₃), 75(C₆H₃⁺); (b)9a: m/z 214(M⁺), 198(M⁺– O), 170(M⁺– CO₂), 154(M⁺– O – CO₂), 142(M⁺– CO₂– CO), 126(M⁺– O – CO₂– CO), 74(C₆H₂⁺); (c)10a: m/z 292(M⁺), 220(M⁺– CO₂– CO), 74(C₆H₂⁺).
12. (a) R. D. Brown, D. E. Pullin, E. H. N. Rice and M. Rodler, J. Am. Chem. Soc., 1985, 117, 7877; (b) P. Botschwina and H. P. Reisenauer, Chem. Phys. Lett., 1991, 183, 217.
13. (a) K. O. Patten, Jr. and L. Andrews, J. Phys. Chem., 1986, 90, 3910; (b) H. Bai and B. S. Ault, J. Phys. Chem., 1992, 96, 9169; (c) J. L. Laboy and B. S. Ault, J. Photochem. Photobiol. A: Chem., 1993, 74, 99.
14. Y. Hase, K. Kawai and O. Sala, J. Mol. Struct., 1975, 26, 297.
15. (a) E. Kloster-Jensen, Angew. Chem. Int. Ed. Engl., 1972, 4, 438; (b) E. Kloster-Jensen, H.-J. Haink and H. Christen, Helv. Chim. Acta, 1974, 57, 1731.
16. D. G. Prichard, J. S. Muenter and B. J. Howard, J. Chem. Phys., 1988, 89, 1245.
17. G. P. van der Zwet, M. S. de Groot, F. Baas and J. M. Greenberg, NATO ASI Ser., Ser. C, 1987, 191, 183.
18. C. J. Pouchert, in The Aldrich Library of FT -IR Spectra, Aldrich Chemical Co., Milwaukee, 1st edn., 1989, vol. 3, p. 1579.
19. (a) R. Lindh, T. J. Lee, A. Bernhardsson, B. J. Persson and G. Karlström, J. Am. Chem. Soc., 1995, 47, 7186; (b) R. Lindh and M. Schütz, Chem. Phys. Lett., 1996, 258, 409.
20. E. Kraka and D. Cremer, J. Am. Chem. Soc., 1994, 46, 4929.
21. P. Chen, Angew. Chem., Int. Ed. Engl., 1996, 35, 1478.