title: Unusually Strong Long-Distance Metal-Metal Coupling in Bis(ferrocene)-Containing BOPHY: An Introduction to Organometallic BOPHYs.
abstract: The first organometallic BOPHY (BOPHY=bis(difluoroboron)-1,2-bis{(pyrrol-2-yl)methylene}hydrazine) containing two ferrocene substituents was prepared through a Knoevenagel condensation between tetramethyl substituted BOPHY and ferrocene carboxaldehyde. An unprecedentedly strong long-range (≈17.2 Å) metal-metal coupling in this new complex was investigated using electrochemical, spectroelectrochemical, and chemical oxidation methods. Electrochemical data is indicative of a 200 mV separation between the first and the second ferrocene-centered oxidation processes. Formation of the mixed-valence states and appearance and disappearance of two NIR bands were observed during stepwise oxidation of the first organometallic BOPHY. The electronic structure and the nature of the excited states in this new chromophore were studied by DFT and TDDFT calculations.
authors.affiliation: Department of Chemistry and Biochemistry, University of Minnesota - Duluth, 1039 University Drive, Duluth, MN 55812 (USA).
authors.forename: Hannah M
authors.initials: HM
authors.lastname: Rhoda
authors.affiliation: Department of Chemistry, University of Akron, Akron, Ohio 44312-3601 (USA).
authors.forename: Kullapa
authors.initials: K
authors.lastname: Chanawanno
authors.affiliation: Department of Chemistry and Biochemistry, University of Minnesota - Duluth, 1039 University Drive, Duluth, MN 55812 (USA).
authors.forename: Alexander J
authors.initials: AJ
authors.lastname: King
authors.affiliation: Department of Chemistry and Biochemistry, University of Minnesota - Duluth, 1039 University Drive, Duluth, MN 55812 (USA).
authors.forename: Yuriy V
authors.initials: YV
authors.lastname: Zatsikha
authors.affiliation: Department of Chemistry, University of Akron, Akron, Ohio 44312-3601 (USA). ziegler@uakron.edu.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Ziegler
authors.affiliation: Department of Chemistry and Biochemistry, University of Minnesota - Duluth, 1039 University Drive, Duluth, MN 55812 (USA). vnemykin@d.umn.edu.
authors.forename: Victor N
authors.initials: VN
authors.lastname: Nemykin
keywords: BOPHY; density functional calculations; ferrocene; metal-metal coupling; mixed-valency