Porphyrins in 1,3-Dipolar Cycloaddition Reactions. Synthesis of New Porphyrin-Chlorin and Porphyrin-Tetraazachlorin Dyads Ana M. G. Silva, † Paula S. S. Lacerda, † Augusto C. Tome ´, † Maria G. P. M. S. Neves, † Artur M. S. Silva, † Jose ´ A. S. Cavaleiro,* ,† Elena A. Makarova, ‡ and Evgeny A. Lukyanets ‡ Department of Chemistry, UniVersity of AVeiro, 3810-193 AVeiro, Portugal, and Organic Intermediates and Dyes Institute, 1/4 B. SadoVaya str., 103787 Moscow, Russia jcaValeiro@dq.ua.pt ReceiVed June 8, 2006 N-(Porphyrin-2-ylmethyl)glycine was synthesized and used as precursor of azomethine ylide, which was trapped with several dipolarophiles. The reaction of that azomethine ylide with dimethyl fumarate afforded the expected adduct. However, with 1,4-benzo- and 1,4-naphthoquinones only dehydrogenated adducts were isolated. Also, the reaction of that ylide with meso-tetrakis(pentafluorophenyl)porphyrin and tetraazaporphine allowed access to novel porphyrin-chlorin and porphyrin-tetraazachlorin dyads. Introduction During the past decade, various synthetic strategies have been developed in order to make different multiporphyrin systems where the porphyrin units are directly linked by meso-meso, meso-, and - positions, oligoporphyrins with fused π-systems and arrays bearing rigid and flexible spacers. 1 In such a way, a large range of multiporphyrin systems with linear, cyclic, and cross-linked geometries have been synthesized. The interest in the synthesis of multiporphyrin materials 2 (dimers and other oligomers) arise from their potential application as models in light harvesting, 3 as molecular photonic and electronic wires, 4 as catalysts, 5 and as photosensitizers for photodynamic therapy (PDT). 6 In the past few years, we have shown that porphyrins can participate in 1,3-dipolar cycloadditions in two different ways: they react as dipolarophiles with azomethine ylide 2, generated from N-methylglycine and formaldehyde, to give pyrrolidine- fused chlorins 3 (route I, Scheme 1), 7 and they can be used as precursors of the porphyrinic azomethine ylide 5, which reacts with dipolarophiles to give -pyrrolidine-meso-tetraphenylpor- phyrins 7 (route II, Scheme 1). 8 In the absence of dipolarophiles, * To whom correspondence should be addressed. Tel: + 351 234 370 717. Fax: + 351 234 370 084. † University of Aveiro. ‡ Organic Intermediates and Dyes Institute. (1) Lacerda, P. S. S.; Silva, A. M. G.; Tome ´, A. C.; Neves, M. G. P. M. S.; Silva, A. M. S.; Cavaleiro, J. A. S.; Llamas-Saiz, A. L. Angew. Chem., Int. Ed. 2006, 45, 5487 and references cited therein. (2) Recent review: Elemans, J. A. A. W.; van Hameren, R.; Nolte, R. J. M.; Rowan, A. E. AdV. Mater. 2006, 18, 1251. (3) Recent review: Kobuke, Y. Eur. J. Inorg. Chem. 2006, 12, 2333. Recent examples: (a) Hori, T.; Aratani, N.; Takagi, A.; Matsumoto, T.; Kawai, T.; Yoon, M.-C.; Yoon, Z. S.; Cho, S.; Kim, D.; Osuka, A. Chem. Eur. J. 2006, 12, 1319. (b) Hajjaj, F.; Yoon, Z. S.; Yoon, M.-C.; Park, J.; Satake, A.; Kim, D.; Kobuke, Y. J. Am. Chem. Soc. 2006, 128, 4612. (c) Maes, W.; Vanderhaeghen, J.; Smeets, S.; Asokan, C. V.; Van Renterghem, L. M.; Du Prez, F. E.; Smet, M.; Dehaen, W. J. Org. Chem. 2006, 71, 2987. (4) Recent example: Thamyongkit, P.; Yu, L.; Padmaja, K.; Jiao, J.; Bocian, D. F.; Lindsey, J. S. J. Org. Chem. 2006, 71, 1156. (5) Recent example: Chavan, S. A.; Maes, W.; Gevers, L. E. M.; Wahlen, J.; Vankelecom, I. F. J.; Jacobs, P. A.; Dehaen, W.; De Vos, D. E. Chem. Eur. J. 2005, 11, 6754-6762. (6) Recent review: Nyman, E. S.; Hynninen, P. H. J. Photochem. Photobiol., B 2004, 73, 1. (7) Silva, A. M. G.; Tome ´, A. C.; Neves, M. G. P. M. S.; Silva, A. M. S.; Cavaleiro, J. A. S. J. Org. Chem. 2005, 70, 2306. 8352 J. Org. Chem. 2006, 71, 8352-8356 10.1021/jo0611770 CCC: $33.50 © 2006 American Chemical Society Published on Web 10/05/2006