Novel heterometallic polymers induced by host-guest cations: X-ray structures of [(18-crown-6)KAgWs₄]_n and [{(18-crown-6)Ba(DMF)₄}(AG₂w₂S ₈)]_n

Two novel sulfido-heterometallic polymers, [(18-crown-6)KAgWS₄]_n 1 and [{(18-crown-6)Ba(DMF)₄}(Ag₂W₂S ₈)]_n 2, induced by supramolecular cations, were synthesized through the reaction of 18-crown-6, silver nitrate, ammonium thiotungstate and potassium nitrate or barium nitrate, respectively. Both 1 and 2 were characterized by elemental analyses, IR, UV-vis, ¹H NMR spectra and X-ray single crystal determination. Compound 1 crystallizes in the orthorhombic space group Cmc2₁ with a = 14.163(5), b = 15.063(7), c = 10.550(3) Å, Z = 4, d = 2.135 g cm^-3, R₁ = 0.0487, wR₂ = 0.1257 (on 1602 observed reflections with I > 2σ(I)). It has a wave-like one-dimensional anion complex polymer configuration, on which is appended the supramolecular cation, [(18-crown-6)K]⁺ arrangement. Compound 2 crystallizes in the monoclinic space group P2₁ with a = 8.4524(1), b = 18.0486(1), c = 15.6294(1) Å, β = 93.299(1)°, Z = 4, d = 4.280 g cm^-3, R₁ = 0.0323, wR₂ = 0.0619 (on 5941 observed reflections with I > 2σ(I)). It consists of a zigzag sulfido-silver-tungsten anion chain and a [(18-crown-6)Ba(DMF)₄]²⁺ ion, in which the barium ion is coordinated by the six oxygen atoms of the crown ether molecule and four oxygen atoms of the DMF molecules.