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Updated: Nov 24, 2025
The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
Octaboraneyl [Ni(H)(diphosphine)2]+ Complexes: Exploiting Phosphine Ligand Lability for Hydride Transfer to an [NAD]+
Joseph A Zurakowski1, Moulika Bhattacharyya1, Denis M Spasyuk2
1Department of Chemistry and Biochemistry, The University of Windsor, 401 Sunset Avenue, Windsor, Ontario N9B 3P4, Canada.
Abstract:
Ligand design represents a central tenet of synthetic chemistry, wherein simple modification can lead to major differences in reactivity. Herein, we describe the preparation of two bis(diphosphino)nickel(II) hydride complexes that contain eight pendant boranes in their secondary coordination sphere, [Ni(H)(P2BR4)2]+ (R = Cy or Mes; Mes = 2,4,6-trimethylphenyl). Divergent reactivity of the cyclohexyl analogue toward the [NAD]+ model, 3-acetyl-N-benzylpyridinium bromide ([BNAcP]Br), is underscored. While [Ni(H)(P2BCy4)2]+ undergoes rapid hydride transfer, the related species [Ni(H)(dnppe)2]+ [dnppe = 1,2-bis(di-n-propylphosphino)ethane] and adduct [Ni(H)(P2BCy4)2(DMAP)8]+ (DMAP = 4-N,N-dimethylaminopyridine) exhibit no such reactivity. This borane-appended nickel(II) hydride distinguishes itself from its "all-alkyl" cousins and provides future opportunities for the design of [Ni(H)(diphosphine)2]+ reagents for hydride transfer.
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