1775
Inorg. Chem. 1986, 25, 1775-1778
Contribution from the Laboratoire de Synthbe et d'Etudes Physicochimiques, Universite des Sciences et Techniques du Languedoc, 34060 Montpellier Cedex, France
New Complexes of Ruthenium(I1) with a Tetrapyrazolic Macrocycle C. Marzin,*+ G . Tarrago,+ M. Gal,+ I. Zidane? T. Hours,' D. Lerner,* C. Andrieux,s H. Gampp,s and J. M. Savdants Received October 16, 1985
The preparation and properties of Ru(I1) complexes Ru(TZ)XY(PF~)~ are described (TZ = 2,7,12,17-tetramethyl-l,6,11,16tetraazaporphyrinogen; X = Me2S0, Y = Me,SO or pyridine; X = CH,CN, Y = CH$N or pyridine; X = Y = pyridine or 4,4'-bipyridine). Thermal and photochemical labilizations of the axial ligands X and Y are studied. 'H NMR spectroscopy allows easy complex structural characterization. Electronic spectral data and redox potential measurements are discussed.
Introduction
Scheme I
complexes, mainly those with polypyridine, have been recently the subject of extensive studies due to their potential utilization as photosensitizers in energy conversion processes.' Comparatively, Ru(I1) complexation of macrocycles has not been widely investigated with the exception of porphyrin2-I6 and p h t h a l o ~ y a n i n e ~complexes. ~ ~ ~ - ~ ~ This interest comes from the greater stability of ruthenium complexes compared to iron ones, making them easier to use in the study of hemoprotein models. Characteristics of this kind of complex are that the transition metal is inside the porphyrin or phthalocyanine cavity and that the axial ligands are thermally and photochemically labile except in the case of a carbonyl ligand. Most of the studies concern porphyrin complexes containing a t least one axial carbonyl ligand mainly because they are easier to prepare, but some authors developed the synthesis of complexes with different axial ligands such as pyridine,2,4J4*'7-20 imida~ole,~ p h ~ s p h i n e , ~ ! ' ~dimethyl J ~ J ~ sulfoxide,I7J8 and a~etonitri1e.l~The other macrocyclic complex studies concern saturated tetraaza macrocycles of the cyclam f a m i l ~ ~for l - which ~ ~ stable Ru(I1) complexes are rather difficult to obtain. It seems to us of great interest to extend these investigations to other macrocycles having such properties that the Ru(I1) complexes obtained would be stable and that the axial ligands would be less labile than in porphyrin ones; as a first example we chose a macrocycle with pyrazole units, the tetraazaporphyrinogen lZ4 in which the four sp2 nitrogen atoms and the aromatic nature Ruthenium(I1)
DM S O
7 2a
RuCI3
,/--
CH3CN
2b
--??%
2b
1
2a R u I O M S ~ ~ ~ C I ~
Scheme I1 2' RulT211DMS012
A in C H p C N
R",,ZI,CH3CN12'
in E t TO- 2Hk/h -H,1O ' 2
PYP
R"!T21,CH3CN!I
PY!2*
3h
In the present contribution we report on the synthesis and physicochemical and photochemical studies of some Ru(I1) com-
Me
~
of pyrazole should stabilize Ru(I1) complexes over Ru(II1) ones by the occurrence of back-bonding. The cavity size of 1 is about the same as that of a porphyrin but they differ from each other by their electronic structure: 1 contains four isolated aromatic heterocycles whereas a porphyrin is an aromatic macrocycle; furthermore, macrocycle 1 must give charged Ru(I1) complexes compared to the neutral porphyrin complexes described. These distinct properties should give to these two types of macrocycles different s-acceptor and o-donor capacities, which greatly influence the axial ligand lability,25 leading, we hoped, to a better stability of the axial ligands in the tetraazaporphyrinogen 1.
'
UniversitE. des Sciences et Techniques du Languedoc, Montpellier; UA 468 au CNRS. 'Ecole Nationale Supirieure de Chimie de Montpellier; UA 418 au CNRS. $Labratoired'Elecrochimie, Universit.5 Paris VII; UA 438 au CNRS.
0020-1669/86/ 1325- 1775$01.50/0
~
~
~
~
~~~~~
Kalyanasundaram, K. Coord. Chem. Reo. 1982.46, 159. Seddon, K. R. Coord. Chem. Rev. 1982,41,79. Seddon, E. A.; Seddon, K. R. In Topics in Inorganic and General Chemistry; Elsevier: Amsterdam, 1984; p 19. Chow, B. C.; Cohen, I. A. Bioinorg. Chem. 1971, I , 57. Hopf, F. R.; O'Brien, T. P.; Scheidt, W. R.; Whitten, D. G. J . Am. Chem. SOC.1975, 97, 277. Antipas, A.; Buchler, J. W.; Gouterman, M.; Smith, P. D. J . Am. Chem. SOC.1978. 100. 3015. Young, R.~C.; Nagle, J. K.; Meyer, T. J.; Whitten, D. G. J . Am. Chem. SOC.1978, 100, 4773. Faller, J. W.; Chen, C. C.; Malerich, C. J. J . Znorg. Biochem. 1979, ZZ, 151.
Rillema, D. P.; Nagle, J. K.; Barringer, L. F.; Meyer, T. J. J . Am, Chem. SOC.1981. 103. 56. Ball, R. G.;Domazetis,'G.; Dolphin, D.; James, B. R.; Trotter, J. J. Am. Chem. SOC.1981, 103, 1556. Pompso, F.; Carruthers, D.; Stynes, D. V. Inorg. Chem. 1982, 21,4245. Kadish. K. M.: Leaaett, D. J.; Chana, D. Inora. Chem. 1982,21.3618. Malinski, T.; ChaGi D.; Bottomley,t.A.; Kaaish, K. M. Inorg. Chem. 1982, 21, 4248. Holloway, C. E.; Stynes, D. V.; Vuik, C. P. J . Chem. Soc., Dalfon Trans. 1982, 95. Barley, M.; Becker, J. Y.; Domazetis, G.; Dolphin, D.; James, B. R. Can. J . Chem. 1983, 61, 2389. Collman, J. P.; Barnes, C. E.; Sweaston, P. N.; Ibers, J. A. J . Am. Chem. SOC.1984. 106. 3500. Barley, M.; Dolphin, D'.; James, B. R.; Kirmaier, C.; Holten, D. J . Am. Chem. SOC.1984, 106, 3931. Ariel, S . ; Dolphin, D.; Domazetis, G.; James, B. R.; Leung, T. W.; Rettig, S . J.; Trotter, J.; Williams, G. M. Can. J . Chem. 1984, 62, 755.
0 1986 American Chemical Society
1776 Inorganic Chemistry, Vol. 25, No. 11, 1986
Marzin et ai.
Table I. ‘ H N M R Data for Noncomplexed Ligands and Complexed” Macrocycles in CD3CNb
W-U HIuvr)
comod
5.83 6.49 6.48 6.44 6.49
Ru(TZ) (4,4’-bpy)’+ (2f)
CHdovr)
CHAmac)
2.16 (+0.66) (+0.65) (+0.61) (+0.66)
2.52 2.53 2.46 2.47
X‘
YC
4.85 (+0.36) (+0.37) (+0.30) (+0.31)
6.48 (+0.65)
2.45 (+0.29)
6.48 (+0.65)
2.51 (+0.35)
8.50 (a),7.06 (D), 7.48 (y) 8.63 (a),7.58 (p) 5.45 (+0.60) 2.42, 2.47 5.34 (+0.49) 2.49 4.75 (-0.10) 7.45 (a)(-1.05), 6.98 (p) (-0.08), 7.60 (7) (+0.1 4.95 (+0.10) 2.47 7.28 ( a ) (-1.22) 5.50 (+0.65)‘ 7.09 (8) (+0.03) 7.74 (y) (+0.26) 4.81 (-0.04) 2.45 7.33 ( a ) (-1.17) 5.32 (+0.47)e 6.95 (p) (-0.11) 7.61 (y) (+0.13) 4.85 (0.00) 7.65 (a)(-0.98) 7.37 ( P ) (-0.21) 8.72 (a‘)(+0.09)d 7.59 (p’) (+O.Ol)d
In all cases the anion is PF6-. bValues in parentheses are the chemical shift differences between the complexed and noncomplexed ligand.
