In situ Alkylation of 4,4'-Bipyridine in Hydrothermal Synthesis of an Iodoplumbate Inorganic-organic Hybrid with Fluorescence

A novel 1-D iodoplumbate hybrid, 2(Pb_3I_9)~(3-)·3(C_(14)H_(18)N_2)~(2+) 1, has been hydrothermally synthesized and characterized by IR spectra, TGA and single-crystal X-ray diffraction.Complex 1 crystallizes in monoclinic, space group P2_1/c, with α = 12.057(2), b = 14.024(3), c=24.742(5) (A), β= 90.48(3)°, V = 4183.6(14) (A)~3, Z = 4, R = 0.0477 and wR = 0.0800. The title compound consists of 1-D chains (Pb_3I_9)n~(3n-) parallel to the 100] direction and stacks of alkylated 4,4'-bipyridium cations running along the 011] direction. Each anionic chain is surrounded by six arrays of alkylated 4,4'-bipyridium cations through extensive C-H…I atypical hydrogen-bonding interactions to afford an interesting 3-D supramolecular network. Significant fluorescent property of the compound was observed at room temperature.