87607-70-3Relevant articles and documents
Extended structure of indium(III) protoporphyrin IX acetate mimics dimer structure of hematin anhydride
Dodd, Erin L.,Bohle, D. Scott
, p. 36 - 42 (2016)
A complex of indium(III) protoporphyrin IX acetate was prepared and characterized crystallographically as its pyridine solvate. The structure of the 5-coordinate In complex is dimeric through a strong bridging hydrogen bond between the propionic acid group of one porphyrin unit and the carbonyl of the In-bound acetate, leading to a structure that mimics the reciprocal dimer structure of the malaria pigment hemozoin with an expanded frame. Inter-dimer π-stacking and hydrogen bonding interactions of the propionic acid groups are the dominant structural features. This result, following the report of reciprocal dimers of gallium(III) protoporphyrin IX species, indicates that this is a common motif for metalloprotoporphyrin IX species.
Soluble diamagnetic model for malaria pigment: Coordination chemistry of gallium(III)protoporphyrin-IX
Bohle, D. Scott,Dodd, Erin L.,Pinter, Tyler B. J.,Stillman, Martin J.
, p. 10747 - 10761 (2013/01/15)
The facile axial ligand exchange properties of gallium(III) protoporphyrin IX in methanol solution were utilized to explore self-association interactions by NMR techniques. Structural changes were observed, as well as competitive behavior with the ligands acetate and fluoride, which differed from that seen with the synthetic analogue gallium(III) octaethylporphyrin which lacks acid groups in its side-chains and has less solution heterogeneity as indicated by absorption and MCD spectroscopies. The propionic acid side chains of protoporphyrin IX are implicated in all such interactions of PPIX, and both dynamic metal-propionic interactions and the formation of propionate-bridged dimers are observed. Fluoride coordination provides an unusual example of slow ligand exchange, and this allows for the identification of a fluoride bridged dimer in solution. An improved synthesis of the chloride and hydroxide complexes of gallium(III) protoporphyrin IX is reported. An insoluble gallium analogue of hematin anhydride is described. In general, the interactions between solvent and the metal are found to confer very high solubility, making [Ga(PPIX)] + a useful model for ferric heme species.
Gallium(III) and indium(III) octaethylporphyrin dimeric complexes with a single μ-hydroxo bridge: Synthesis, structure and stability in anion-containing organic media
Parzuchowski, Pawe? G.,Kampf, Jeff W.,Ro?niecka, Ewa,Kondratenko, Yevgeniy,Malinowska, Elzbieta,Meyerhoff, Mark E.
, p. 302 - 313 (2008/10/09)
The synthesis and single-crystal X-ray structures of the hydroxo-bridged complexes (μ-hydroxo)-bis(octaethylporphinato)gallium(III)perchlorate {[Ga(OEP)]2OH}ClO4 and (μ-hydroxo)- bis(octaethylporphinato)indium(III)tetrakis[3,5-bis-(trifluoromethyl)phenyl] borate {[In(OEP)]2OH}TFPB are reported. These complexes are prepared by the titration of monomeric metalloporphyrin species in dichloromethane with diluted perchloric acid or by the addition of stoichiometric amounts of the tetraphenylborate derivative salt. The structures show that complexes of two metalloporphyrins are joined by a single protonated metal-oxygen-metal bridge with a nearly 150° bridge angle. The porphyrin rings of the dimers form dihedral angles of 15° Ga(III) and 23° In(III). In contrast to previously reported analogous dimeric Mn(III) and Fe(III) structures, the porphyrin rings of the present dimers are twisted by a much greater torsion angle of nearly 22°. In dichloromethane, high stability of the dimers is observed in the presence of perchlorate, but dissociation of the dimer species to monomers is found with increasing concentrations of halogen anions. This corresponds well with the observed anion selectivities recently reported for both electrochemical and optical anion sensors prepared with the respective Ga(III) and In(III) octaethylporphyrins in polymeric films.
