Synthesis, Structure and Properties of Two Novel 2D Zinc(II) Coordination Polymers based on Fluconazole and Benzene Carboxylic Acid

Experimental

All chemicals were commercial materials of analytical grade and used as received. The FT-IR spectrum was obtained on a Nicolet 520 FT–IR spectrophotometer Fourier transform infrared spectroscopy in the 4000-400 cm-1 regions, using KBr pellets. Elemental analysis for C, H, N was carried out on a Perkin-Elmer 2400 II elemental analyzer. Powder X-ray diffraction (XRD) patterns were obtained using a pinhole camera (Anton Paar) operating with a point focused Ni-filtered Cu Kɑ radiation in the 2θ range from 5° to 50° with a scan rate of 0.08° per second. The optical properties were analyzed by UV-vis diffuse reflectance spectroscopy using a UV-vis spectrophotometer (Cary-500, Varian Co.), in which BaSO4 was used as the internal standard. Fluorescence spectra were recorded with a F-2500 FL Spectrophotometer analyzer. Thermogravimetric analyzer was performed on a Perkin-Elmer TG/DTA 6300 thermal analyzer under N2 atmosphere at a heating rate of 10 ℃/min in the temperature range 30-1000 ℃.

For preparation of complex 1, a mixture of fluconazole (153 mg, 0.5 mmol), isophthalic acid (83 mg, 0.5 mmol), ZnCl2 (136 mg, 1.0 mmol), 15 mL H2O, and 4 mL ethanol was sealed in a 30 mL Teflon-lined stainless steel container. An aqueous solution of sodium hydroxide was added dropwise with stirring to adjust the pH value of the solution being 6.0. Kept under autogenous pressure at 150 ℃ for 3 days before cooling to room temperature at a rate of 5 ℃ h-1; Then the transparent crystals of 1 were obtained. The crystals were isolated, washed with alcohol three times, and dried in a vacuum desiccator using silicagel (yield 72.6%, based on Zn). Elemental analysis Calcd (%) for C21H16F2N6O5Zn: C 47.08, H 3.01, N 15.69. Found (%): C 47.11, H 3.04, N 15.73. IR (KBr, cm-1): 3430w, 3159w, 3124w, 1611s, 1565s, 1500m, 1477w, 1359s, 1276m, 1130m, 1102w, 994w, 965w, 740m, 674w, 658w.

For preparation of complex 2, the same synthetic procedure as that for 1 was used except that isophthalic acid (83 mg, 0.5 mmol) was replaced by H3btc (105 mg, 0.5 mmol) (yield 65.1%, based on Zn). Elemental analysis Calcd (%) for C22H16F2N6O7Zn: C 45.58, H 2.78, N 14.50. Found (%): C 45.63, H 2.82, N 14.57. IR (KBr, cm-1): 3157w, 3128w, 1703s, 1627m, 1570m, 1542w, 1502w, 1456w, 1428w, 1366s, 1277m, 1186w, 1131m, 1099w, 1078w, 997m, 968w, 862w, 735m, 675m.

X-ray diffraction data for the complex were collected on on a Bruker SMART CCD diffractometer equipped with Graphite-monochromatized Mo Kɑ radiation (λ = 0.71073 Å) at 296(2) K. A high quality crystal of the complex was selected and was mounted on a glass fiber. Collect the data sets with the ω scan technique. Empirical absorption corrections were applied using the SADABS program.14 The structure was solved by direct methods and all non-hydrogen atoms were refined with anisotropic thermal parameters by a full-matrix least-squares based on F2 using SHELXTL package. 15 All non-hydrogen atoms were refined anisotronically. Crystallographic data for the structures reported here have been deposited with CCDC (Deposition No. CCDC-940683 (1) and CCDC-940684 (2)). These data can be obtained free of charge via http://www.ccdc.cam.ac.uk/conts/retrieving. html or from CCDC, 12 Union Road, Cambridge CB2 1EZ, UK, E-mail: deposit@ccdc.cam.ac.uk