A selective and sensitive reagent of 2-pyridine carboxaldehyde isonicotinyl hydrazone(2-PYAINH) was synthesized and studied for the spectrophotometric determination of nickel, copper, cobalt, and iron in detail. At ...A selective and sensitive reagent of 2-pyridine carboxaldehyde isonicotinyl hydrazone(2-PYAINH) was synthesized and studied for the spectrophotometric determination of nickel, copper, cobalt, and iron in detail. At a pH value of 7.0, 9,0, 9.0, and 8.0, respectively, which greatly increased the selectivity; nickel, copper, cobalt, and iron reacted with 2-PYAINH to form a 1:2 yellow-orange, 1:2 yellow-green, 1:2 yellow and 1:1 yellow complexes, with absorption peaks at 363, 352, 346, and 359 nm, respectively. Under the optimal conditions, Beer's law was obeyed over the ranges of 0.01-1.4, 0.01-1.5, 0.01-2.7, and 0.01-5.4 mg/L respectively. The apparent molar absorptivity and Sandell's sensitivities were 8.4×10^4, 5.2×10^4, 7.1×10^4, and 3.9×10^4 L·mol^-l·cm^-1, respectively, and 0.00069, 0.0012, 0.00078, and 0.0014 μg·cm2, respectively. The detection limits were found to be 0.001, 0.002, 0.003, and 0.01 mg/L, respectively. The detailed study of various interfering ions to make the method more sensitive was carried out and selective and several real samples were analyzed with satisfactory results.展开更多
The Schiff base pyridine-2-carboxaldehyde-4-aminoantipyrine (CI7H16N4O 1) and its perchlorate (C17H17N4O·ClO4 2) have been prepared and characterized by elemental analysis, IR spectra and single-crystal X-ray...The Schiff base pyridine-2-carboxaldehyde-4-aminoantipyrine (CI7H16N4O 1) and its perchlorate (C17H17N4O·ClO4 2) have been prepared and characterized by elemental analysis, IR spectra and single-crystal X-ray crystallography analysis. Both 1 and 2 crystallize in the monoclinic system, space group P21/c. For 1, a = 8.6820(12), b = 24.934(3), c = 7.0064(10) A,, β= 97.942(3)°, V = 1502.2(4) A^3, Z = 4, Dc = 1.293 g/cm^3, F(000) = 616,μ = 0.084 mm^-1, the final R = 0.0592 and wR = 0.1244. For 2, a = 5.9302(2), b = 20.347(7), c = 14.663(6) A, β= 90.200(9)°, V= 1769.201) A^3, Z = 4, Dc = 1.475 g/cm^3, F(000) = 816, μ = 0.254 mm^-1, the final R = 0.0533 and wR = 0.0819. As expected, both molecular structures of 1 and 2 adopt a trans configuration about the central C=N double bond. 2 is an ionic compound with the protonation at N(1) of pyridine-2-carboxaldehyde-4- aminoantipyrine.展开更多
The synthesis of 1,4,5,8-tetramethoxynaphthalene-2-carboxaldehyde,an intermediate of shikonin was investigated.1,4,5,8-tetramethoxynaphthalene was prepared from the oxidation of 1,5-dinitronaphthalene and the reaction...The synthesis of 1,4,5,8-tetramethoxynaphthalene-2-carboxaldehyde,an intermediate of shikonin was investigated.1,4,5,8-tetramethoxynaphthalene was prepared from the oxidation of 1,5-dinitronaphthalene and the reaction product naphthazarin was directly methylated without been purified.The title compound was obtained by the formylation of 1,4,5,8-tetramethoxynaphthalene.The overall yield was 38.5% based on 1,5-dinitronaphthalene.展开更多
文摘A selective and sensitive reagent of 2-pyridine carboxaldehyde isonicotinyl hydrazone(2-PYAINH) was synthesized and studied for the spectrophotometric determination of nickel, copper, cobalt, and iron in detail. At a pH value of 7.0, 9,0, 9.0, and 8.0, respectively, which greatly increased the selectivity; nickel, copper, cobalt, and iron reacted with 2-PYAINH to form a 1:2 yellow-orange, 1:2 yellow-green, 1:2 yellow and 1:1 yellow complexes, with absorption peaks at 363, 352, 346, and 359 nm, respectively. Under the optimal conditions, Beer's law was obeyed over the ranges of 0.01-1.4, 0.01-1.5, 0.01-2.7, and 0.01-5.4 mg/L respectively. The apparent molar absorptivity and Sandell's sensitivities were 8.4×10^4, 5.2×10^4, 7.1×10^4, and 3.9×10^4 L·mol^-l·cm^-1, respectively, and 0.00069, 0.0012, 0.00078, and 0.0014 μg·cm2, respectively. The detection limits were found to be 0.001, 0.002, 0.003, and 0.01 mg/L, respectively. The detailed study of various interfering ions to make the method more sensitive was carried out and selective and several real samples were analyzed with satisfactory results.
基金supported by the NSF of Guangxi Province (No. 0575046, 0575049)the Program for New Century Ten-Hundred-Thousand Excellent Talents of Guangxi (No. 2003223)+1 种基金the National Natural Science Foundation of China (No. 20361002, 30460153) as well as TRAPOYTNCET-04-0836 of Chinese Ministry of Education
文摘The Schiff base pyridine-2-carboxaldehyde-4-aminoantipyrine (CI7H16N4O 1) and its perchlorate (C17H17N4O·ClO4 2) have been prepared and characterized by elemental analysis, IR spectra and single-crystal X-ray crystallography analysis. Both 1 and 2 crystallize in the monoclinic system, space group P21/c. For 1, a = 8.6820(12), b = 24.934(3), c = 7.0064(10) A,, β= 97.942(3)°, V = 1502.2(4) A^3, Z = 4, Dc = 1.293 g/cm^3, F(000) = 616,μ = 0.084 mm^-1, the final R = 0.0592 and wR = 0.1244. For 2, a = 5.9302(2), b = 20.347(7), c = 14.663(6) A, β= 90.200(9)°, V= 1769.201) A^3, Z = 4, Dc = 1.475 g/cm^3, F(000) = 816, μ = 0.254 mm^-1, the final R = 0.0533 and wR = 0.0819. As expected, both molecular structures of 1 and 2 adopt a trans configuration about the central C=N double bond. 2 is an ionic compound with the protonation at N(1) of pyridine-2-carboxaldehyde-4- aminoantipyrine.
文摘使用溶剂热法,吡啶-2-甲醛缩氨基硫脲与Co(C lO4)2.6H2O反应制备了Co(Ⅲ)配合物[Co(C7H7N4S)2](C lO4),并用元素分析、红外光谱和紫外光谱对配合物进行表征。采用SRB法试验了配体和配合物对体外口腔黏膜癌细胞(KB)的敏感性,结果表明浓度为0.16 m g/L时,配合物对细胞杀伤力大于配体,金属与配体作用可能具有加合作用。
文摘The synthesis of 1,4,5,8-tetramethoxynaphthalene-2-carboxaldehyde,an intermediate of shikonin was investigated.1,4,5,8-tetramethoxynaphthalene was prepared from the oxidation of 1,5-dinitronaphthalene and the reaction product naphthazarin was directly methylated without been purified.The title compound was obtained by the formylation of 1,4,5,8-tetramethoxynaphthalene.The overall yield was 38.5% based on 1,5-dinitronaphthalene.