Title
Aggregation Properties of Nitroporphyrins: Comparisons between Solid-State and Solution Structures
Document Type
Article
Publication Date
1-1-1993
Abstract
Previous NMR spectroscopic studies on the aggregation properties of metalloporphyrins suggested that monosubstituted octaethylporphyrin (OEP) derivatives with substituents capable of inducing charge polarization form tail-to-tail type dimers in solution. Such dimers have implications as model compounds for the photosynthetic reaction center. Crystallographic studies on a series of 5-NO2-OEP compounds show that the zinc(II) complexes can indeed form dimers of the proposed type in the solid state. A four-coordinated planar zinc(II) 5-nitrooctaethylporphyrin and the corresponding methanol complex showed strong aggregation in the solid state. The pyridine complex and the free-base porphyrin showed no strong aggregation. Crystal data: 5-NO2-OEP (7), C36H45N5O2, Mr = 579.8, triclinic, P1̄, a = 9.374(3) Å, b = 13.794(6) Å, c = 14.221(4) Å, α = 104.69(3)°, β = 106.39(2)°, γ = 104.57(3)°, V= 1599.7(10) Å3, Z = 2, Dx = 1.204 Mg·m−3, λ(Mo Ka) = 0.710 73 Å,µ = 0.080 mm−1, 130 K, R = 0.078 for 3328 reflections with F > 3.5σ(F); Zn(5-NO2-OEP)(C5H5N) (9-C5H5N), C41H48N6O2Zn, Mr = 722.6, triclinic, P1̄, a = 9.942(3) Å, b = 10.722(4) Å, c = 17.744(5) Å α = 81.74(3)°, β = 78.67(3)°, γ = 83.99(3)°, V = 1829.5(8) Å3, Z = 2, Dx = 1.32 Mg·m−3, λ(Mo Kα) = 0.710 73 Å µ = 0.731 mm−1, 293 K, R = 0.063 for 5161 reflections with F > 3σ(F); Zn(5-NO2-OEP) (9), C36H43N5O2Zn, Mr = 643.15, monoclinic, P21/c, a = 9.721(3) Å b = 21.807(6) Å, c = 15.378(4) Å, ² = 102.99(2)°, V = 3176.6 Å, Z = 4, Dx = 1.322 Mg·m−3, λ(Cu Kα) = 1.541 84 Å µ = 0.138 mm−1, 293 K, R = 0.067 for 3017 reflections with F > 3σ(F); Zn(5-NO2-OEP)(CH3OH) (9-CH3OH), C37H47N5O3Zn, M, = 675.2, monoclinic, P21/c, a = 10.540(8) Å b = 14.240(12) Å c = 23.625(16) Å, β = 101.39(5)°, K= 3476(4) Å3 Z = 4, Dx = 1.290 Mg·m−3, λ(Mo Kα) = 0.710 73 Å, µ = 0.749 mm−1, 130 K, R = 0.106 for 3894 reflections with F > 4σ(F). © 1993, American Chemical Society. All rights reserved.
Publication Source (Journal or Book title)
Inorganic Chemistry
First Page
3134
Last Page
3142
Recommended Citation
Senge, M., Eigenbrot, C., Brennan, T., Shusta, J., Scheidt, W., & Smith, K. (1993). Aggregation Properties of Nitroporphyrins: Comparisons between Solid-State and Solution Structures. Inorganic Chemistry, 32 (14), 3134-3142. https://doi.org/10.1021/ic00066a027