title: Tripyrrindione as a Redox-Active Ligand: Palladium(II) Coordination in Three Redox States.
abstract: The tripyrrin-1,14-dione scaffold of urinary pigment uroerythrin coordinates divalent palladium as a planar tridentate ligand. Spectroscopic, structural and computational investigations reveal that the tripyrrindione ligand binds as a dianionic radical, and the resulting complex is stable at room temperature. One-electron oxidation and reduction reactions do not alter the planar coordination sphere of palladium(II) and lead to the isolation of two additional complexes presenting different redox states of the ligand framework. Unaffected by stability problems common to tripyrrolic fragments, the tripyrrindione ligand offers a robust platform for ligand-based redox chemistry.
authors.affiliation: Department of Chemistry and Biochemistry, University of Arizona, 1306 E. University Blvd., Tucson AZ 85721 (USA).
authors.forename: Ritika
authors.initials: R
authors.lastname: Gautam
authors.affiliation: Department of Chemistry and Biochemistry, University of Arizona, 1306 E. University Blvd., Tucson AZ 85721 (USA).
authors.forename: Jonathan J
authors.initials: JJ
authors.lastname: Loughrey
authors.affiliation: Department of Chemistry and Biochemistry, University of Arizona, 1306 E. University Blvd., Tucson AZ 85721 (USA).
authors.forename: Andrei V
authors.initials: AV
authors.lastname: Astashkin
authors.affiliation: Department of Chemistry, University of Nevada, Reno NV 89577 (USA).
authors.forename: Jason
authors.initials: J
authors.lastname: Shearer
authors.affiliation: Department of Chemistry and Biochemistry, University of Arizona, 1306 E. University Blvd., Tucson AZ 85721 (USA). tomat@email.arizona.edu.
authors.forename: Elisa
authors.initials: E
authors.lastname: Tomat
mesh_terms: D056831:Coordination Complexes / Q000737:chemistry*; D008024:Ligands; D008958:Models, Molecular; D015394:Molecular Structure; D010084:Oxidation-Reduction; D010165:Palladium / Q000737:chemistry*; D011728:Pyridones / Q000737:chemistry*; D011789:Quantum Theory
chemical_list: D056831:Coordination Complexes; D008024:Ligands; D011728:Pyridones; C000610425:tripyrrin-1,14-dione; D010165:Palladium
keywords: oligopyrroles; redox non-innocence; redox-active ligands; tripyrrindione; uroerythrin