Crystal and molecular structures of some mono-meso-substituted free base and zinc(II)octaalkylporphyrins
Studies on highly substituted porphyrins bearing eight β-substituents and at least one bulky meso-substitutent have shown that peripheral steric strain leads to considerable macrocycle distortion. While this is well established for porphyrins with dodecasubstitution; the situation is less clear for nonasubstituted porphyrins with meso-substituents such as methyl, aryl or ester groups. In order to further study this situation we have investigated the conformation of nonasubstituted porphyrins with small meso-substitutents by determination of the crystal structures of: 2,3,7,8,12,13,17,18-octaethyl-5-(N-succinimidyl)porphyrin, 1; 2,7,12,17-tetraethyl-3,8,13,18-tetramethyl-5-methoxymethylporphyrin, 2; pyridine (2,7,12,17-tetraethyl-3,8,13,18-tetramethyl-5-methoxymethylporphyrinato) zinc(II), 3; methanol(5-acetoxy-2,7,12,17-tetracthyl-3,8,13,18-tetramethyl-porphyrinato)- zinc(II) methanol solvate, 4; and (2,3,7,8,12,13,17,18-octaethyl-5-methylporphyrinato)zinc(II), 5. The compounds show only small deviations from planarity which might be due to packing effects, however, all compounds show some degree of rhomboic elongation of the porphyrin core.
Publication Source (Journal or Book title)
Zeitschrift fur Kristallographie
Senge, M., Forsyth, T., & Smith, K. (1996). Crystal and molecular structures of some mono-meso-substituted free base and zinc(II)octaalkylporphyrins. Zeitschrift fur Kristallographie, 211 (3), 176-185. Retrieved from https://digitalcommons.lsu.edu/chemistry_pubs/1743