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Updated: Mar 16, 2026
Author Spotlight: Experimental Approaches for the Synthesis of Low-Valent Metal-Organic Frameworks from Multitopic Phosphine Linkers
Published on: May 12, 2023
Structural and electronic trends for five coordinate 1(st) row transition metal complexes: Mn(ii) to Zn(ii) captured
Titel Jurca1, Sarah Ouanounou, Wei-Chih Shih
1Department of Chemistry and Biomolecular Sciences, Center for Catalysis Research and Innovation, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada. darrrin@uottawa.ca.
Abstract:
The preparation and characterization of a series of divalent 3d transition metal complexes supported by a tridentate planar bis(iminopyridine) ligand are reported. The complexes {2,6-[PhC[double bond, length as m-dash]N(tBu2C6H3)]2C5H3N}MBr2 (M = Mn, Fe, Co, Ni, Cu, Zn), 1-6, were characterized by single crystal X-ray structural studies revealing complexes with pentacoordinate distorted square pyramidal coordination environments. This assembly of complexes provided a unique array for examining the relationship between experimental structure and computed electronic structure. While experimental structural features basically correlated with the Irving-Williams series, some clear deviations were rationalized through the computational analysis. A balance of bis(imino)pyridine/metal with bonding/antibonding π interactions was used to explain the divergent directions of Fe(ii)-N and Co(ii)-N bond lengths. Similarly, orbital details were used to justify the opposing change in Cu-Brap and Cu-Brbas bond lengths. Furthermore, computational analysis provided a unique method to document a surprising low bond order for the M-N bonds of bis(imino)pyridine ligand in this series.
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