Novel crystal engineering in the crown ether nickel maleonitriledithiolate complexes, synthesis and crystal structures of [Na(N15C5)_2]_2[Ni(mnt)_2] and [Na(N15C5)]_2[Ni(mnt)_2]

摘要

Reactions of N15C5 (2,3-naphtho-15-crown-5) with nickel maleonitriledithiolate sodium complex, Na_2[Ni(mnt)_2] (mnt = maleonitriledithiolate) using different molar ratios (2 :1 and 4:1) afforded two structurally different complexes [Na(N15C5)_2]_2[Ni(mnt)_2] (1) and [Na(N 15C5)]_2[Ni(mnt)_2] (2). The sandwich [Na(N15C5)_2]~+ and mono-capped [Na(N15C5)]~+ organic cations are observed in the crystals of 1 and 2, respectively, with the same [Ni(mnt)_2]~(2-) inorganic conteranions. It is these structurally different organic cations that lead to the dissimilar structures. Complex 1 exhibits a one-dimensional (1D) chain-like structure assembled by intercantionic {[Na(N15C5)_2]~+}_(propor. to) pi-pi stacking interactions and electrostatic interactions, while 2 displays a novel two-dimensional (2D) corrugated sheet-like structure constructed by Na-N interactions which occur between the [Na(N15C5)]~+ inorganic cations and [Ni(mnt)_2]~(2-) inorganic anions.