Synthesis, crystal structure and spectral analysis of crown ether platinum bis(dithiolate) complexes [Na(N15C5)2]2[Pt(mnt)2] and [Na(N15C5)]2[Pt(i-mnt)2]

The reactions of 2,3-naphtho-15-crown-5 (N15C5) with Na2[Pt(L)2] [L=1,2-dicyanoethylene-1,2-dithiolate (mnt) or 1,1-dicyanoethylene-2,2-dithiolate (i-mnt)] afford two complexes [Na(N15C5)2]2[Pt(mnt)2] (1) and [Na(N15C5)]2[Pt(i-mnt)2] (2). They are characterized by elemental analysis, FT-IR, UV-visible spectra and single crystal X-ray diffraction. 1 crystallizes in the monoclinic, space group P21/c with a=15.616(11), b=20.481(14), c=12.910(9) Å, β=103.298(11)°, V=4018(5) Å3, Z=2 and R1(wR2)=0.0390 (0.0808). 2 crystallizes in the triclinic, space group Pī with a=8.360(3), b=12.892(5), c=12.899(5) Å, α=115.472 (5), β=106.053(6)°, γ=91.981(6)°, V=1187.2(8) Å3, Z=1 and R1(wR2)=0.0365 (0.0775). The [Na(N15C5)2]+ sandwich complex cations of 1 are assembled into a novel 1D zigzag chain by alternating π-π stacking interactions and the resulting cationic chains are linked into a 2D network by the bridging [Pt(mnt)2]2− complex anions through weak C-H⋯S hydrogen bonds. For 2, the [Na(N15C5)]+ mono-capped complex cations act as the bridges linking the [Pt(i-mnt)2]2− anions into a 1D infinite chain through Na-N bonds and S⋯C and S⋯π interactions are observed in the chain.