One-electron redox processes of the Cu(II) chelate of 3,8,12,17-tetraethyl-2,7,13,18-tetramethylbilin- 1,19-dione

Tetrahedron Letters

Volumn 38, Issue 4, 1997, Pages 669-672

  Anglada, Maria Carme ^a   Farrera, Joan Anton ^a   Ribó, Josep M ^a  

^a UNIVERSITY OF BARCELONA   (Spain)

Author keywords

[No Author keywords available]

Indexed keywords

BILIVERDIN; CHELATE; COPPER COMPLEX; LIGAND;

ARTICLE; CHEMICAL REACTION; CHEMICAL STRUCTURE; ELECTROLYSIS; ELECTRON SPIN RESONANCE; OXIDATION REDUCTION REACTION;

EID: 0031023823     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4039(96)02388-X     Document Type: Article

References (26)

1. IUPAC, Nomenclature of Tetrapyrroles, Pure Appl. Chem. 1987, 59, 779-832.
2. For Mn, Fe, Co, Ni, Cu and Zn chelates see (a) Falk, H.; Schlederer, T. Liebigs Ann. Chem. 1979, 1560-1570.
3. (b) Bonfiglio, J. V.; Bonnett, R.; Buckley, D. G.; Hamzetash, D.; Hursthouse, M. B.; Abdul Malik, K. M. Tetrahedron 1983, 39, 1865-1874.
4. (c) Balch, A.; Latos-Grazinsky, L.; Noll, B. C; Olmstead, M. M.; Safari, N. J. Am. Chem. Soc. 1993, 115, 9056-9061.
5. (d) Balch, A.; Mazzanti, M.; Noll, B. C; Olmstead, M. M. J. Am. Chem. Soc. 1993, 115, 12206-12207.
6. (e) Balch, A.; Mazzanti, M.; Noll, B. C.; Olmstead, M. M. J. Am. Chem. Soc. 1994, 116, 9114-9122;
7. f) Jaumà, A.; Escuer, A.; Farrera, J.-A.; Ribó, J. M. Monatsh. Chem. 1996, in press.
8. In respect to the magnetic behaviour of metalloporphyrins and metalloporphyrinato cation radicals see e. g. (a) Scholtz, W. Z.; Reed, C. A.; Lee, Y. A.; Scheidt, R.; Lang, G. J. Am. Chem. Soc. 1982, 104, 6791-793.
9. (b) Godziela, G. M.; Goff, H. M. J. Am. Chem. Soc. 1986, 108, 2237-2243.
10. (c) Erler, B. S.; Scholtz, W. F.; Lee, Y. A.; Scheidt, R.; Reed, C. A. J. Am. Chem. Soc. 1987, 709, 2644-2652.
11. (d) Song, H.; Reed, C. A.; Scheidt, W. R. J. Am. Chem. Soc. 1989, 111, 6865-6866.
12. (e) Renner, M. W.; Barkigia, K. M.; Zhang, Y.; Medforth, C. J.; Smith, K. M.; Fajer, J. J. Am. Chem. Soc. 1994, 116, 8582-8592.
13. II chelates corresponds to a dideprotonated ligand, with one of the end lactam rings tautomerized to the hydroxyimino form.
14. 2e also points towards a trideprotonated ligand.
15. II chelate of the radical of the ligand. However, the lower redox potentials corresponding to Co and Ni could allow the presence of valence tautomerism between the states (III) and (II).
16. (a) Razuvaev, G. A.; Cherkasov, V. K.; Abakumov, G. A. J. Organomet. Chem. 1978, 160, 361-371.
17. (b) Kaim, W.; Rall, J. Angew. Chem. 1995, 107, 47-54; Angew. Chem. Int. Ed. 1996, 35, 43-60.
18. (b) Kaim, W.; Rall, J. Angew. Chem. 1995, 107, 47-54; Angew. Chem. Int. Ed. 1996, 35, 43-60.
19. 3OH, 1:1): No bands were detected at 77 K or 4 K, only a low intensity band could be detected at half-field at 4 K.
20. Density functional calculations were performed using Spartan v.4.1.1 (Wavefunction Inc., Irvine, CA, USA) in a SG R8000 work station.
21. 2 symmetry and in consequence in antiferromagnetic coupling; e.g. the centrosymmetric association, through one of the end lactam rings, of two helices of different sign.
22. 2f shows the well known pathway of bilin-1,19-diones to give bilipurpurins and biliviolins, which has been proposed to occur through such cations; Acero, C.; Ribó, J. M.; Solé, R.; Trull, F. R. Monatsh. Chem. 1993, 124, 401-417.
23. N = 13 G.
24. e. g. the dimer formed by the heteroassociation of a biliverdin with its radical cation has recently been isolated as a stable solid species; Balch, A. L.; Koerner, R.; Olmstead, M. M.; Mazzanti, M.; Safari, N.; Clair, T. St. J.C.S. Chem. Comm. 1995, 643-644.
25. (a) Schmid, R.; McDonagh, A. F. in The Porphyrins, Vol. 6 (Ed. D. Dolphin): Springer, New York, 1979; pp. 257-292.
26. (b) H. Falk, The Chemistry of Linear Oligopyrroles and Bile Pigments: Springer Verlag, Wien, 1989, pp 497-534.