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991.
Xin-Mei Fu  Shu-Gui Dai 《合成通讯》2013,43(16):2455-2460
A new series of task-specific ionic liquids (TSILs) containing hydroxyl groups was prepared and applied for extracting 4-nonylphenol (4-NP) and 4-tert-octylphenol (4-t-OP) in water. These new TSILs showed much greater extraction efficiencies for 4-NP and 4-t-OP than the common typical ionic liquids 1-butyl-3-methylimidazolium hexafluorophosphate ([C4mim][PF6]) and 1-hexyl-3-methylimidazolium hexafluorophosphate ([C6mim][PF6]).

Additional information

ACKNOWLEDGMENTS

This work was supported by the National Natural Science Foundation of China (20377025) and the Scientific Research Foundation of Southwest University of Science and Technology (06ZX7116).  相似文献   
992.
A series of aryl hydroxylactams (2a, 2b, 2d2g, 2i2k, 2m, and 2n) was synthesized by partially reducing aryl cyclic imides in moderate to excellent yields with activated zinc dust alone in acetic acid. This method was regiospecific and can be employed as an alternative for reported methods to partially reduce aryl cyclic imides.  相似文献   
993.
Gaifa Lai  Tao Guo 《合成通讯》2013,43(1):72-76
A convenient, five‐step preparation of 2‐acetyl‐4,5‐difluorothiophene from 2,3‐dibromothiophene is described.  相似文献   
994.
The first examples of lariat calix[4]-1,3-aza-crowns with chiral amino acid groups as branched chains (5a and 5b) were designed and synthesized via a 1 + 1 addition reaction of calix[4]-1,3-substituted benzaldehyde derivative (4) and amino acid hydrazide derivatives (3a and 3b) in yields of 70% and 75%, respectively. The preliminary extraction experiments suggested that hosts 5a and 5b possessed good complexation abilities for α-amino acids.   相似文献   
995.
J-AT nucleoside-based organogelators 1a and 1b were designed and synthesized. They were endowed with unparalleled superiority to natural nucleobase analogues 26 to gelate aromatic solvents due to their excellent self-assembly properties. The J-AT nucleoside-based organogelators showed a specific self-complementary base pair recognition characteristic. The gel stabilities of 1a and 1b were drastically influenced by adenine analogue 2, hardly affected by thymine analogue 3, uracil analogue 4, cytosine analogue 5, and mildly interrupted by guanine analogue 6.  相似文献   
996.
Two coordination polymers (CPs), {[Zn2(BMB)(5‐AIPA)2] · 2H2O}n( 1 ) and [Zn(BMB)(5‐NIPA)]n( 2 ) {BMB = 1, 4‐bis[(2‐methyl‐imidazol‐1‐yl)methyl]benzene, 5‐AIPA = 5‐aminoisophthalic acid, 5‐NIPA = 5‐nitroisophthalic acid}, were synthesized under hydrothermal conditions. Compound 1 displays a 2D double‐layer structure, which is packed into a 3D supramolecule by interlayer hydrogen bonds and π–π stacking interactions. Compound 2 displays a threefold interpenetrating 3D network, which is composed of left‐handed helical chains and two types of meso‐helical chains along different directions.  相似文献   
997.
The intriguing multi‐ligand compound [Cu(IMI)4Cl]Cl ( 1 ) with the ligand imidazole (IMI) was synthesized and characterized by elemental analysis and FT‐IR spectroscopy. The crystal structure was determined by X‐ray single crystal diffraction and the crystallographic data showed that the compound belongs to the monoclinic P21/n space group [α = 8.847(2) Å, b = 13.210(3) Å, c = 13.870(3) Å, and β = 90.164(3)°]. Furthermore, the CuII ion is five‐coordinated by four nitrogen atoms from four imidazole ligands and a chlorine atom. The thermal decomposition mechanism was determined based on differential scanning calorimetry (DSC) and thermogravimetric (TG‐DTG) analysis. The non‐isothermal kinetics parameters were calculated by the Kissinger's method and Ozawa's method, respectively. The energy of combustion, enthalpy of formation, critical temperature of thermal explosion, entropy of activation (ΔS), enthalpy of activation (ΔH), and free energy of activation (ΔG) were measured and calculated.  相似文献   
998.
999.
A series of heterometallic LnIII–SbIII edta‐containing compounds with the formulas [Sb2(edta)2Ln]NO3 · nH2O [edta = ethylenediaminetetraacetate; Ln = Eu, n = 7 ( 1 ); Gd, n = 7.5 ( 2 ) and Tb, n = 8 ( 3 )] were synthesized and characterized by elemental analyses (EA), powder X‐ray diffraction (PXDP), Fourier transform infrared spectroscopy (FT‐IR), and thermogravimetric analyses (TGA). Their fluorescence and magnetic properties were also studied. The thermal analysis demonstrates the compounds formation of the antimony, lanthanide ions, and edta4– ligands. FT‐IR spectra reveal that the antimony and lanthanide ions are connected through the carboxylate bridges. The studies of luminescence properties show that compounds 1 and 3 exhibit typical luminescence in the visible region. Furthermore, magnetic properties reveal compounds 2 and 3 have weak ferromagnetic behavior.  相似文献   
1000.
The Fourier transform infrared-attenuated total reflectance (FTIR-ATR) difference spectra of aqueous MgSO4, Na2SO4, NaCl and MgCl2 solutions against pure water were obtained at various concentrations. The difference spectra of the solutions showed distinct positive bands and negative bands in the O–H stretching region, indicating the influences of salts on structures of hydrogen-bonds between water molecules. Furthermore the difference spectra of MgCl2 solutions against NaCl solutions and those of MgSO4 solutions against Na2SO4 solutions with the same concentrations of anions (Cl? or SO 4 2? , respectively) allowed extracting the structural difference of the first hydration layer between Mg2+ and Na+. Using SO 4 2? as a reference ion, structural information of the first hydration layer of the Cl? anion was obtained according to the difference spectra of MgCl2 solutions against MgSO4 solutions and those of NaCl solutions against Na2SO4 solutions containing the same concentrations of cations (Mg2+ or Na+, respectively). The positive peak at ~3,407 cm?1 and negative peak at ~3,168 cm?1 in these spectra indicated that adding Cl? decreased the strongest hydrogen-bond component and increased the relatively weaker one.  相似文献   
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