Syntheses, crystal structures, thermal analysis, and spectra of two complexes containing bis(maleonitriledithiolate)nickelate(II) anion and di-substituted chlorobenzyl triphenylphosphinium cation

ABSTRACT

Two new ion-pair metal–bis(dithiolene) complexes, with the formulas [2,4-BiClBzTPP]₂[Ni(mnt)₂](1) and [2,6-BiClBzTPP]₂[Ni(mnt)₂](2) ([2,4-BiClBzTPP]⁺ = 2,4-bichlorobenzyl)triphenylphosphonium, [2,6-BiClBzTPP]⁺ = 2,6-bichlorobenzyl)triphenylphosphonium, and mnt²⁻ = maleonitriledithiolate) have been synthesized and characterized by spectroscopic and physicochemical methods as well as X-ray diffraction. Two complexes crystallize in the triclinic space group P-1 and the central Ni(II) ion shows a distorted square planar coordination geometry. The anions (A) and cations (C) in complex 1 stack together into a columnar structure with ···A-CC-A-CC-A··· sequence. Lattice stability is provided by weak interactions observed in 1 and 2 such as C–H···N, C–H···Cl, C–H···S, C–H···Ni, and C–H···π hydrogen bonds which result in the forming of a 3D network structure. Thermal analysis reveals that 1 and 2 are stable up to 211°C and 208°C, respectively, and the final decomposition product of two complexes is metal nickel.

KEYWORDS:

• Bis(maleonitriledithiolate)nickelate(II) anion
• di-substituted benzyl triphenylphosphinium
• weak interactions
• 3D structures

Funding

This work has been partially supported by the Science and Technology Project (No. 2014A010105037) from the Guangdong Science and Technology Department and the undergraduates' innovative training program in University (No.201610564246) from South China Agricultural University.