Synthesis and Structural Characterization of Several Ruthenium Porphyrin Nitrosyl Complexes

The synthesis, X-ray crystal structures, and some spectroscopic
and chemical properties of the nitrosylruthenium(II) porphyrin complexes Ru(TPP)(NO)(ONO),
Ru(TPP)(NO)(OH), Ru(OEP)(NO)(ONO), and
Ru(OEP)(NO)(OH) (TPP = tetraphenylporphyrinato dianion; OEP =
octaethylporphyrinato dianion) derived from the analogous
Ru(II) carbonyl complexes are reported. Also described are
experiments which quantitatively demonstrate that
N2O is formed as a product of the synthesis scheme and that
NO serves as the principal oxidant in the transformation
of N(II) to N(III). The two TPP complexes are isostructural and
consist of columns of molecules stacked along
the c axis. The two OEP complexes are also
isostructural and can be considered as layers of OEP
complexes
stacked along the b axis with solvent molecules situated at
the cavities between layers. The nitrite ions are
coordinated in a unidentate fashion through the oxygen atom.
Crystal data for Ru(TPP)(NO)(ONO) (1): 
M =
789.79, space group I4/m (No. 87), a
= 13.6529(6) Å, c = 9.7904(5) Å,
V = 1825.0(2) Å3, Z = 2,
ρ = 1.437 g
cm-3, purple bipyramid, 2θmax
= 50.0°, R(F) = 4.87% for 86 parameters
and 838 reflections with I >
2σ(I).
Crystal data for Ru(TPP)(NO)(OH) (2): 
M = 760.79, space group I4/m (No.
87), a = 13.5423(4) Å, c =
9.7150(4) Å, V = 1781.7(1) Å3, Z
= 2, ρ = 1.418 g cm-3, dark red plate,
2θmax = 50.0°, R(F) = 3.92%
for 83 parameters
and 811 reflections with I > 2σ(I).
Crystal data for
Ru(OEP)(NO)(ONO)·CH2Cl2
(3):  M = 794.77, space group
P21 (No. 4), a = 10.7687(2)
Å, b = 21.0320(2) Å, c =
8.5936(2) Å, β = 102.683(1)°, V =
1898.85(6) Å3, Z =
2, ρ = 1.390 g cm-3, black plate,
2θmax = 50.0°, R(F) = 6.23%
for 453 parameters and 4702 reflections with I
> 2σ(I). Crystal data for
Ru(OEP)(NO)(OH)·C2H5OH
(4):  M = 726.91, space group
P21 (No. 4), a =
10.8474(7) Å, b = 21.002(1) Å, c =
8.3646(5) Å, β = 103.571(1)°, V =
1852.4(2) Å3, Z = 2, ρ = 1.303 g
cm-3, brown
plate, 2θmax = 45.0°, R(F) =
6.74% for 421 parameters and 3527 reflections with I >
2σ(I).