Related Experiment Video
Updated: Aug 20, 2025
Preparation of SNS CobaltII Pincer Model Complexes of Liver Alcohol Dehydrogenase
Published on: March 19, 2020
Electronic and Structural Variations of a Nickel(0) N-Heterocyclic Phosphenium Complex in Comparison to Group 10
Leah K Oliemuller1, Curtis E Moore1, Christine M Thomas1
1Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States.
Abstract:
The bonding interactions and electronic structure of a diphosphine pincer ligand featuring an N-heterocyclic phosphenium/phosphido (NHP±) central moiety with nickel are explored. Treating Ni(COD)2 with the pincer ligand [PPP]Cl in the presence of a two-electron phosphine donor ligand PMe3 generates chlorophosphine complex (PPClP)Ni(PMe3) (2a). The cationic Ni complex [(PPP)Ni(PMe3)][BPh4] (3a) can be prepared by subsequent halide abstraction from 2a with NaBPh4. The assignment of 3a as a Ni0/NHP+ complex, based on analysis of structural parameters and computational investigations, lies in contrast to its previously reported group 10 MII/NHP- (M = Pd, Pt) analogues. The activation of O-H bonds across the Ni-PNHP bond is demonstrated by the addition of isopropanol to afford the metal hydride species [(PPOP)Ni(PMe3)(H)][BPh4] (4). Notably, the installation of a P-H bond in the NHP unit by treatment of 2a with LiAlH4 yields (PPHP)Ni(PMe3) (6). The ambiphilic nature of the P-H bond was demonstrated through reactivity studies of P-H bond cleavage in comparison to a Pd analogue (PPHP)Pd(PPh3) (8).
Related Concept Videos
02:42Valence Bond Theory
02:34Structural Isomerism
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can...
02:54Coordination Compounds and Nomenclature
02:58Crystal Field Theory - Octahedral Complexes
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
02:46Crystal Field Theory - Tetrahedral and Square Planar Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...