Competition Between Azido Cleavage and Triplet Nitrene Formation in Azidomethylacetophenones
Ranaweera A. A. Upul Ranaweera A , Yu Zhao A , Sivaramakrishnan Muthukrishnan A , Christopher Keller A and Anna D. Gudmundsdottir A BA Department of Chemistry, University of Cincinnati, Cincinnati, OH 45221-0172, USA.
B Corresponding author. Email: anna.gudmundsdottir@uc.edu
Australian Journal of Chemistry 63(12) 1645-1655 https://doi.org/10.1071/CH10331
Submitted: 9 September 2010 Accepted: 10 November 2010 Published: 6 December 2010
Abstract
Photolysis of p- and m-azidomethylacetophenone (1a, 1b) in argon-saturated solutions yields predominantly imine 2a, 2b, whereas irradiation of 1a, 1b in oxygen-saturated solutions results in heterocycles 3a, 3b, aldehydes 4a, 4b and nitriles 5a, 5b. Density functional theory calculations place the energy of the first and second excited state of the triplet ketones (T1K and T2K) in 1a, 1b in close proximity to each other. The triplet transition state for cleaving the C–N bond in 1a, 1b to form azido and benzyl radicals 1aB, 1bB is located only 3 kcal mol–1 (1 kcal = 4.184 kJ) above T1K, indicating that azido cleavage is feasible. The calculations place the energy of the triplet azido group (TA) in 1a, 1b ∼25 kcal mol–1 below T1K; thus, this process is also easily accessible via energy transfer. Further, the transition state barrier for TA to expel N2 and form triplet nitrenes is less than 1 kcal mol–1 above TA in 1a, 1b. Laser flash photolysis of 1a, 1b reveals the formation of the triplet excited ketones of 1a, 1b, which decay to form benzyl radicals 1aB, 1bB and triplet alkylnitrenes. The triplet ketones and the benzyl radicals are quenched with molecular oxygen at rates close to diffusion, whereas the triplet nitrenes react more slowly with oxygen (∼5 × 105 M–1 s–1). We conclude that the triplet alkylnitrenes intercept the benzyl radicals to form 2 in argon-saturated solution, whereas the benzyl radicals are trapped to form 4 in oxygen-saturated solution; thus, the triplet nitrenes react with oxygen to form 3.
References
[1] W. Lwowski (Ed.), Nitrenes 1970 (Wiley-Interscience: New York, NY).[2] M. S. Platz, Acc. Chem. Res. 1995, 28, 487.
| Crossref | GoogleScholarGoogle Scholar |
[3] N. P. Gritsan, M. S. Platz, Chem. Rev. 2006, 106, 3844.
| Crossref | GoogleScholarGoogle Scholar | 16967923PubMed |
[4] W. Lwowski, Ann. N. Y. Acad. Sci. 1980, 346, 491.
| Crossref | GoogleScholarGoogle Scholar |
[5] K. A. Schnapp, M. S. Platz, Bioconjug. Chem. 1993, 4, 178.
| Crossref | GoogleScholarGoogle Scholar | 7873650PubMed |
[6] F. Z. Seela, Z. Naturforsch. C 1976, 31, 389.
| 134581PubMed |
[7] J. K. Jorgensen, A. Stori, K. Redford, E. Ommundsen, Polymer 2005, 46, 12256.
| Crossref | GoogleScholarGoogle Scholar |
[8] A. S. Al Akhrass, R.-V. Ostaci, Y. Grohens, E. Drockenmuller, G. Reiter, Langmuir 2008, 24, 1884.
| Crossref | GoogleScholarGoogle Scholar | 18205421PubMed |
[9] A. V. Jadhav, C. G. Gulgas, A. D. Gudmundsdottir, Eur. Polym. J. 2007, 43, 2594.
| Crossref | GoogleScholarGoogle Scholar |
[10] A. J. Osteraas, D. A. Olsen, J. Appl. Polym. Sci. 1969, 13, 1537.
| Crossref | GoogleScholarGoogle Scholar |
[11] A. J. Osteraas, D. A. Olsen, Nature 1969, 221, 1140.
| Crossref | GoogleScholarGoogle Scholar |
[12] J. S. Mecomber, R. S. Murthy, S. Rajam, P. N. D. Singh, A. D. Gudmundsdottir, P. A. Limbach, Langmuir 2008, 24, 3645.
| Crossref | GoogleScholarGoogle Scholar | 18294015PubMed |
[13] W. Subhan, P. Rempala, R. S. Sheridan, J. Am. Chem. Soc. 1998, 120, 11528.
| Crossref | GoogleScholarGoogle Scholar |
[14] Magnetic Properties of Organic Materials 1999 (Ed. P. M. Lahti) (Marcel Dekker, Inc.: New York, NY).
[15] Azides and Nitrenes Reactivity and Utility 1984 (Ed. E. F. V. Scriven) (Academic Press: Orlando, FL).
[16] P. N. D. Singh, S. M. Mandel, J. Sankaranarayanan, S. Muthukrishnan, M. Chang, R. M. Robinson, P. M. Lahti, B. S. Ault, A. D. Gudmundsdottir, J. Am. Chem. Soc. 2007, 129, 16263.
| Crossref | GoogleScholarGoogle Scholar | 18034493PubMed |
[17] (a) P. N. D. Singh, S. M. Mandel, R. M. Robinson, Z. Zhu, R. Franz, B. S. Ault, A. D. Gudmundsdottir, J. Org. Chem. 2003, 68, 7951.
| Crossref | GoogleScholarGoogle Scholar | 14535770PubMed |
(b) S. M. Mandel, J. A. Krause Bauer, A. D. Gudmundsdottir, Org. Lett. 2001, 3, 523.
| Crossref | GoogleScholarGoogle Scholar |
[18] R. F. Klima, A. V. Jadhav, P. N. D. Singh, M. Chang, C. Vanos, J. Sankaranarayanan, M. Vu, N. Ibrahim, E. Ross, S. McCloskey, R. S. Murthy, J. A. Krause, B. S. Ault, A. D. Gudmundsdottir, J. Org. Chem. 2007, 72, 6372.
| Crossref | GoogleScholarGoogle Scholar | 17655357PubMed |
[19] J. Sankaranarayanan, L. N. Bort, S. M. Mandel, P. Chen, J. A. Krause, E. E. Brooks, P. Tsang, A. D. Gudmundsdottir, Org. Lett. 2008, 10, 937.
| Crossref | GoogleScholarGoogle Scholar | 18254638PubMed |
[20] R. F. Klima, A. D. Gudmundsdottir, J. Photochem. Photobio., A 2004, 162, 239.
| Crossref | GoogleScholarGoogle Scholar |
[21] (a) J. Sankaranarayanan, S. Rajam, C. M. Hadad, A. D. Gudmundsdottir, J. Phys. Org. Chem. 2010, 23, 370.
| Crossref | GoogleScholarGoogle Scholar |
(b) S. Muthukrishnan, S. M. Mandel, J. C. Hackett, P. N. D. Singh, C. M. Hadad, J. A. Krause, A. D. Gudmundsdottir, J. Org. Chem. 2007, 72, 2757.
| Crossref | GoogleScholarGoogle Scholar |
[22] A. Corsaro, G. Buemi, U. Chiacchio, G. Perrini, V. Pistara, R. Romeo, Tetrahedron 1996, 52, 7885.
| Crossref | GoogleScholarGoogle Scholar |
[23] (a) P. S. Engel, J. Am. Chem. Soc. 1970, 92, 6074.
| Crossref | GoogleScholarGoogle Scholar |
(b) W. K. Robbins, R. H. Eastman, J. Am. Chem. Soc. 1970, 92, 6076.
| Crossref | GoogleScholarGoogle Scholar |
(c) W. K. Robbins, R. H. Eastman, J. Am. Chem. Soc. 1970, 92, 6077.
| Crossref | GoogleScholarGoogle Scholar |
(d) M. Veerman, M. J. E. Resendiz, M. A. Garcia-Garibay, Org. Lett. 2006, 8, 2615.
| Crossref | GoogleScholarGoogle Scholar |
(e) R. Ruzicka, L. Barakova, P. Klan, J. Phys. Chem. B 2005, 109, 9346.
| Crossref | GoogleScholarGoogle Scholar |
(f) C. A. Chesta, J. Mohanty, W. M. Nau, U. Bhattacharjee, R. G. Weiss, J. Am. Chem. Soc. 2007, 129, 5012.
| Crossref | GoogleScholarGoogle Scholar |
[24] M. J. Frisch, G. W. Trucks, H. B. Schlegel, G. E. Scuseria, M. A. Robb. J. R. Cheeseman, G. Scalmani, V. Barone, B. Mennucci, G. A. Petersson, H. Nakatsuji, M. Caricato, X. Li, H. P. Hratchian, A. F. Izmaylov, J. Bloino, G. Zheng, J. L. Sonnenberg, M. Hada, M. Ehara, K. Toyota, R. Fukuda, J. Hasegawa, M. Ishida, T. Nakajima, Y. Honda, O. Kitao, H. Nakai, T. Vreven, J. A. Montgomery, Jr, J. E. Peralta, F. Ogliaro, M. Bearpark, J. J. Heyd, E. Brothers, K. N. Kudin, V. N. Staroverov, R. Kobayashi, J. Normand, K. Raghavachari, A. Rendell, J. C. Burant, S. S. Iyengar, J. Tomasi, M. Cossi, N. Rega, N. J. Millam, M. Klene, J. E. Knox, J. B. Cross, V. Bakken, C. Adamo, J. Jaramillo, R. Gomperts, R. E. Stratmann, O. Yazyev, A. J. Austin, R. Cammi, C. Pomelli, J. W. Ochterski, R. L. Martin, K. Morokuma, V. G. Zakrzewski, G. A. Voth, P. Salvador, J. J. Dannenberg, S. Dapprich, A. D. Daniels, Ö. Farkas, J. B. Foresman, J. V. Ortiz, J. Cioslowski, D. J. Fox, Gaussian 09 RA 2009 (Gaussian, Inc.: Wallingford, CT).
[25] C. Lee, W. Yang, R. G. Parr, Phys. Rev. B 1988, 37, 785.
| Crossref | GoogleScholarGoogle Scholar |
[26] A. D. Becke, J. Chem. Phys. 1993, 98, 5648.
| Crossref | GoogleScholarGoogle Scholar |
[27] R. G. Parr, Y. Weitao, Density Functional Theory in Atoms and Molecules 1989 (Oxford University Press: Oxford).
[28] J. K. Labanowksi, J. W. Andzelm, Density Functional Methods in Chemistry 1991 (Springer-Verlag: New York, NY).
[29] J. B. Foresman, M. Head-Gordon, J. A. Pople, M. J. Frisch, J. Phys. Chem. 1992, 96, 135.
| Crossref | GoogleScholarGoogle Scholar |
[30] R. Bauernschmitt, R. Ahlrichs, Chem. Phys. Lett. 1996, 256, 454.
| Crossref | GoogleScholarGoogle Scholar |
[31] R. E. Stratmann, G. E. Scuseria, M. J. Frisch, J. Chem. Phys. 1998, 109, 8218.
| Crossref | GoogleScholarGoogle Scholar |
[32] B. Mennucci, E. Cances, J. Tomasi, J. Phys. Chem. B 1997, 101, 10506.
| Crossref | GoogleScholarGoogle Scholar |
[33] C. J. Cramer, D. G. Truhlar, Chem. Rev. 1999, 99, 2161.
| Crossref | GoogleScholarGoogle Scholar | 11849023PubMed |
[34] E. Cancès, B. Mennucci, J. Chem. Phys. 2001, 114, 4744.
| Crossref | GoogleScholarGoogle Scholar |
[35] J. Tomasi, B. Mennucci, R. Cammi, Chem. Rev. 2005, 105, 2999.
| Crossref | GoogleScholarGoogle Scholar | 16092826PubMed |
[36] J. B. Gallivan, Can. J. Chem. 1972, 50, 3601.
| Crossref | GoogleScholarGoogle Scholar |
[37] S. L. Murov, Thesis 1967, University of Chigaco, Chigaco.
[38] S. Srivastava, E. Yourd, J. P. Toscano, J. Am. Chem. Soc. 1998, 120, 6173.
| Crossref | GoogleScholarGoogle Scholar |
[39] W.-H. Fang, D. L. Phillips, ChemPhysChem 2002, 3, 889.
| Crossref | GoogleScholarGoogle Scholar |
[40] S. Muthukrishnan, J. Sankaranarayanan, T. C. S. Pace, A. Konosonoks, M. E. De Michiei, M. J. Meese, C. Bohne, A. D. Gudmundsdottir, J. Org. Chem. 2010, 75, 1393.
| Crossref | GoogleScholarGoogle Scholar | 20113004PubMed |
[41] H. P. Hratchian, H. B. Schlegel, in Theory and Applications of Computational Chemistry: The First 40 Years 2005, pp. 195–249 (Eds C. E. Dykstra, G. Frenking, K. S. Kim, G. Scuseria) (Elsevier: Amsterdam).
[42] K. Fukui, Acc. Chem. Res. 1981, 14, 363.
| Crossref | GoogleScholarGoogle Scholar |
[43] C. Gonzalez, H. B. Schlegel, J. Chem. Phys. 1989, 90, 2154.
| Crossref | GoogleScholarGoogle Scholar |
[44] C. Gonzalez, H. B. Schlegel, J. Phys. Chem. 1990, 94, 5523.
| Crossref | GoogleScholarGoogle Scholar |
[45] J. S. Yadav, J. D. Goddard, J. Chem. Phys. 1986, 84, 2682.
| Crossref | GoogleScholarGoogle Scholar |
[46] Y. Haas, Photochem. Photobiol. Sci. 2004, 3, 6.
| Crossref | GoogleScholarGoogle Scholar | 14743272PubMed |
[47] M. Klessinger, J. Michl, Excited States and Photochemistry of Organic Molecules 1995 (VCH Publisher, Inc.: New York, NY).
[48] W. D. K. Clark, C. Steel, J. Am. Chem. 1971, 93, 6347.
| Crossref | GoogleScholarGoogle Scholar |
[49] T. Y. Liang, G. B. Schuster, J. Am. Chem. Soc. 1987, 109, 7803.
| Crossref | GoogleScholarGoogle Scholar |
[50] E. A. Pritchina, N. P. Gritsan, J. Photochem. Photobiol., A 1988, 43, 165.
| Crossref | GoogleScholarGoogle Scholar |
[51] N. P. Gritsan, E. S. Pritchina, J. Inform. Rec. Mater. 1989, 17, 391.
[52] J. Liu, C. M. Hadad, M. S. Platz, Org. Lett. 2005, 7, 549.
| Crossref | GoogleScholarGoogle Scholar | 15704891PubMed |
[53] J. C. Scaiano, M. J. Perkins, J. W. Sheppard, M. S. Platz, R. L. Barcus, J. Photochem. 1983, 21, 137.
| Crossref | GoogleScholarGoogle Scholar |
[54] J. C. Netto-Ferreira, W. J. Leigh, J. C. Scaiano, J. Am. Chem. Soc. 1985, 107, 2617.
| Crossref | GoogleScholarGoogle Scholar |
[55] T. Wismontski-Knittel, T. Kilp, J. Phys. Chem. 1984, 88, 110.
| Crossref | GoogleScholarGoogle Scholar |
[56] W. J. Leigh, J. A. H. Banisch, M. S. Workentin, J. Chem. Soc. Chem. Commun. 1993, 988.
| Crossref | GoogleScholarGoogle Scholar |
[57] G. Bucher, J. Phys. Chem. A 2008, 112, 5411.
| Crossref | GoogleScholarGoogle Scholar | 18484713PubMed |
[58] G. A. Molander, C.-S. Yun, Tetrahedron 2002, 58, 1465.
| Crossref | GoogleScholarGoogle Scholar |
[59] S. Ganapathy, B. B. V. S. Sekhar, S. M. Cairns, K. Akutagawa, W. G. Bentrude, J. Am. Chem. Soc. 1999, 121, 2085.
| Crossref | GoogleScholarGoogle Scholar |
[60] X. Zhang, G. C. G. Pais, E. S. Svarovskaia, C. Marchand, A. A. Johnson, R. G. Karki, M. C. Nicklaus, V. K. Pathak, Y. Pommier, J. Burke, R. Terrence, Bioorg. Med. Chem. Lett. 2003, 13, 1215.
| Crossref | GoogleScholarGoogle Scholar | 12643946PubMed |
[61] J. B. Foresman, Æ. Frisch, Exploring Chemistry with Electronic Structure Methods, 2nd edn 1996 (Gaussian, Inc.: Pittsburgh, PA).
[62] S. Muthukrishnan, J. Sankaranarayanan, R. F. Klima, T. C. S. Pace, C. Bohne, A. D. Gudmundsdotti, Org. Lett. 2009, 11, 2345.
| Crossref | GoogleScholarGoogle Scholar | 19432450PubMed |