Crystal structure and electrochemical properties of [Ni(bztmpen)(CH3CN)](BF4)2 {bztmpen is N-benzyl- N, N', N'-tris-[(6-methyl-pyridin-2-yl)meth-yl]ethane-1,2-di-amine}

Lin Chen; Gan Ren; Yakun Guo; Ge Sang

doi:10.1107/S2056989017006764

Crystal structure and electrochemical properties of [Ni(bztmpen)(CH₃CN)](BF₄)₂ {bztmpen is N-benzyl- N, N', N'-tris-[(6-methyl-pyridin-2-yl)meth-yl]ethane-1,2-di-amine}

Acta Crystallogr E Crystallogr Commun. 2017 May 9;73(Pt 6):825-828. doi: 10.1107/S2056989017006764. eCollection 2017 Jun 1.

Authors

Lin Chen¹, Gan Ren¹, Yakun Guo¹, Ge Sang²

Affiliations

¹ Science and Technology on Surface Physics and Chemistry Laboratory, Jiangyou 621908, People's Republic of China.
² Institute of Materials, China Academy of Engineering Physics, Jiangyou 621908, People's Republic of China.

Abstract

The mononuclear nickel title complex (acetonitrile-κN){N-benzyl-N,N',N'-tris-[(6-methyl-pyridin-2-yl)meth-yl]ethane-1,2-di-amine}-nickel(II) bis-(tetra-fluor-ido-borate), [Ni(C₃₀H₃₅N₅)(CH₃CN)](BF₄)₂, was prepared from the reaction of Ni(BF₄)₂·6H₂O with N-benzyl-N,N',N'-tris-[(6-methyl-pyridin-2-yl)meth-yl]ethane-1,2-di-amine (bztmpen) in aceto-nitrile at room temperature. With an open site occupied by the aceto-nitrile mol-ecule, the nickel(II) atom is chelated by five N-atom sites from the ligand and one N atom from the ligand, showing an overall octa-hedral coordination environment. Compared with analogues where the 6-methyl substituent is absent, the bond length around the Ni²⁺ cation are evidently longer. Upon reductive dissociation of the acetro-nitrile mol-ecule, the title complex has an open site for a catalytic reaction. The title complex has two redox couples at -1.50 and -1.80 V (versus F_c^+/0) based on nickel. The F atoms of the two BF₄^- counter-anions are split into two groups and the occupancy ratios refined to 0.611 (18):0.389 (18) and 0.71 (2):0.29 (2).

Keywords: crystal structure; electro-catalyst; nickel; poly-pyridine-diamine.