Synthesis and crystal structures of polynuclear complexes of CuI with 1-methyl-1,3-imidazoline-2-thione

Reactions of equimolar solutions of copper(I) halides with 1-methyl-1,3-imidazoline-2-thione (SC4H6N2) in acetonitrile have yielded a trinuclear complex, {Cu3(η1-Br)3(μ-SC4H6N2)3} · CH3CN 1, and 1D polymer, {Cu2(μ-I)2(μ-SC4H6N2)2}n2. The thio-ligands/halogens adopt μ-S, η1-X or μ-X modes. There is weak interaction between trinuclear units {Cu···Br, 3.025 Å} and Cu···Cu contacts lie in the range, 2.974(2)–3.650(2) Å. Polymer 2 has alternating Cu2I2 and Cu2S2 cores involving sulfur/iodine bridging in a twisted ribbon type arrangement with short Cu···Cu distances {2.6912(9) and 2.785(9) Å}, respectively. The polynuclear complexes in dimethyl sulfoxide exhibit intense fluorescent bands {λem = 319 (1) and 322 (2)}.

The 1-methyl-1,3-imidazoline-2-thione (SC4H6N2) with copper(I) halides have formed uncommon polymers under mild conditions. For example, 1-methyl-1,3-imidazoline-2-thione (SC4H6N2) and copper(I) iodide has yielded a 1D polymer, {Cu2(μ-I)2(μ-SC4H6N2)2}n2 with twisted ribbon like chain and exhibition of fluorescent emission line at 322 (λex, 272 nm).Figure optionsDownload as PowerPoint slide