Synthesis and Reactions of Aminoporphyrazines with Annulated Five- and Seven-Membered Rings Sven M. Baum, † Andre ´s A. Trabanco, † Antonio Garrido Montalban, † Aaron S. Micallef, † Chang Zhong, ‡ Hubert G. Meunier, § Klaus Suhling, † David Phillips, † Andrew J. P. White, † David J. Williams, † Anthony G. M. Barrett,* ,† and Brian M. Hoffman* ,‡ Department of Chemistry, Imperial College of Science, Technology and Medicine, South Kensington, London SW7 2AY, U.K., Department of Chemistry, Northwestern University, Evanston, Illinois 60208, and Department of Chemistry, Assumption College, Worcester, Massachusetts 01609 agmb@ic.ac.uk Received September 26, 2002 The novel five- and seven-membered ring appended aminoporphyrazines 3 and 12 have been prepared via mixed Linstead macrocyclization. The structures of both have been unequivocally established by X-ray crystallographic studies. Reductive deselenation of selenadiazole 3 in the presence of 9,10-phenanthrenequinone or 2,3-butanedione results in the formation of pyrazines 6a,b, whereas oxidation of porphyrazine 12 gave the corresponding seco derivative 14. seco- Porphyrazine 14 mediates the generation of singlet oxygen with a quantum yield of 0.74. Introduction The wide interest in molecule-based metals 1 and magnets 2 has led us to consider peripherally substituted porphyrazines 3 (pz) as possible precursors to such ma- terials. As a first step, we have prepared donor-acceptor crystals of octakis(dimethylamino)-pzs with TCNQ 4 and C 60 . 4,5 More recently, we reported the development of a new family of (dimethylamino)-pz/phthalocyanine (pc) hybrids, designed to provide incremental variation of redox chemistry between M[pc] and the octakis(dimethyl- amino) macrocycle. 6 However, X-ray crystal structural analyses of octakis(dimethylamino)-pzs show that steric clash prevents all adjacent dimethylamino groups from simultaneously conjugating with the pz core. 6,7 We rea- soned that if the amino groups were unsubstituted or locked in a cyclic structure they would couple more strongly and therefore make the corresponding porphyra- zines more efficient electron donors. Herein, we report our studies toward the synthesis and reactions of “un- substituted” and “locked” amino-pzs. Results and Discussion Until recently, the preparation of free amino-pzs has been unsuccessful due to the failure of diaminomaleoni- trile to undergo Linstead 8 macrocyclization reactions. However, Ercolani and co-workers 9a have recently shown that tetrakis(selenodiazole)-pzs can be reductively con- verted into their corresponding octa-amino derivatives. Some drawbacks of these symmetrically substituted macrocycles are the poor solubility of the former and low yield and stability of the latter. 10 In addition, they have also reported unsymmetrical porphyrazines with an annulated 1,2,5-selenodiazole ring. 9b To overcome the limitations presented by the octa-amino derivatives, we also chose to examine related unsymmetrical porphyra- zines. Thus, mixed Linstead macrocyclization of 3,4- dicyano-1,2,5-selenodiazole 9 (1) with a 7-fold excess of 2,3- dipropylmaleonitrile 11 (2) in the presence of magnesium butoxide gave the soluble (chlorinated solvents, MeOH, EtOAc) porphyrazine 3 in 42% yield (Scheme 1). † Imperial College. ‡ Northwestern University. § Assumption College. (1) (a) Ferraro, J. R.; Williams, J. M. In Introduction to Synthetic Electrical Conductors; Academic Press: Orlando, FL, 1987. (b) Wil- liams, J. M.; Ferraro, J. R.; Thorn, R. J.; Carlson, K. D.; Geiser, U.; Wang, H. H.; Kini, A. M.; Whangbo, M.-H. In Organic Superconductors (Including Fullerenes): Synthesis, Structure, Properties and Theory; Prentice Hall: Englewood Cliffs, NJ, 1992. (2) (a) Kahn, O. In Molecular Magnetism; VCH: New York, 1993. (b) Crayston, J. A.; Devine, J. N.; Walton, J. C. Tetrahedron 2000, 56, 7829. (3) (a) Andersen, K.; Anderson, M.; Anderson, O. P.; Baum, S.; Baumann, T. F.; Beall, L. S.; Broderick, W. E.; Cook, A. S.; Eichhorn, D. M.; Goldberg, D.; Hope, H.; Jarrell, W.; Lange, S. J.; McCubbin, Q. J.; Mani, N. S.; Miller, T.; Garrido Montalban, A.; Rodriguez-Morgade, M. S.; Lee, S.; Nie, H.; Olmstead, M. M.; Sabat, M.; Sibert, J. W.; Stern, C.; White, A. J. P.; Williams, D. B. G.; Williams, D. J.; Barrett, A. G. M.; Hoffman, B. M. J. Heterocycl. Chem. 1998, 35, 1013. (b) Michel, S. L. J.; Baum, S.; Barrett, A. G. M.; Hoffman, B. M. In Progress in Inorganic Chemistry; Karlin, K. D., Ed.; J. Wiley & Sons: New York, 2001; Vol. 50. (4) Eichhorn, D. M.; Yang, S.; Jarrell, W.; Baumann, T. F.; Beall, L. S.; White, A. J. P.; Williams, D. J.; Barrett, A. G. M.; Hoffman, B. M. J. Chem. Soc., Chem. Commun. 1995, 1703. (5) Hochmuth, D. H.; Michel, S. L. J.; White, A. J. P.; Williams, D. J.; Barrett, A. G. M.; Hoffman, B. M. Eur. J. Inorg. Chem. 2000, 593. (6) Garrido Montalban, A.; Jarrell, W.; Riguet, E.; McCubbin, Q. J.; Anderson, M. E.; White, A. J. P.; Williams, D. J.; Barrett, A. G. M.; Hoffman, B. M. J. Org. Chem. 2000, 65, 2472. (7) Goldberg, D. P.; Garrido Montalban, A.; White, A. J. P.; Williams, D. J.; Barrett, A. G. M.; Hoffman, B. M. Inorg. Chem. 1998, 37, 2873. (8) Linstead, R. P.; Whalley, M. J. Chem. Soc. 1952, 4839. (9) (a) Bauer, E. M.; Ercolani, C.; Galli, P.; Popkova, I. A.; Stuzhin, P. A. J. Porphyrins Phthalocyanines 1999, 3, 371. (b) Kudrik, E. V.; Bauer, E. M.; Ercolani, C.; Chiesi-Villa, A.; Rizzoli, C.; Gaberkorn, A.; Stuzhin, P. A. Mendeleev Commun. 2001, 45. (10) Ercolani, C.; Angeloni, S. J. Porphyrins Phthalocyanines 2000, 4, 474. (11) Lange, S. J.; Nie, H.; Stern, C. L.; Barrett, A. G. M.; Hoffman, B. M. Inorg. Chem. 1998, 37, 6435. 10.1021/jo026484u CCC: $25.00 © 2003 American Chemical Society J. Org. Chem. 2003, 68, 1665-1670 1665 Published on Web 01/28/2003