아조-연료가 연결된 발색성 거대고리 리간드의 합성, 착물형성 및 변색 특성
Synthesus, complexation and coloration characteristics of Azo-Dye coupled chromogenic macrocyclic ligands
아조 연료 발색성거대고리 리간드 합성 착물형성 변색 화학;
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Heavy metal ions have been known to form the stable complexes with crown thioethers and this led to significant improvements in the syntheses of macrocyclic thioethers. Otherwise, little attention have been paid to the corresponding macrocycles for the selective detection of heavy metal ions expecially mercury(II) although the chemistry of the thiaoxa mixed-donor macrocycles itself is an intensive area of study, and numerous related macrocycles as well as their thiaphilic metal ion complexes and sensor systems are known. According to our preliminary work on the reactivity of the O_(2)S_(2)N-donor macrocycle with the metal ions, only the mercury salts in nitrate and perchlorate form stable 1:1 complexes in solid state among the transition and heavy metal ions under investigated. In this standing point, we assumed that the O_(2)S_(2)N-donor macrocyclic skeleton proved to be a good candidate for use as a sensory molecule for Hg(II). This idea could be extended to the spectroscopic or electrochemical detection by the rationally designed macrocycles followed by the synthesis. In practice, a combination of dyes and macrocycles has been important modification of the host to recognize the specific guest by the color change upon complexation. Our interest in the detection of the heavy metal based on the selective complexation has led to the development of the synthesis for S_(2)O_(2)N macrocycles having an azo-pendant group(L^(1), L^(2), L^(3)). In chapter 1, the out line of the azo-pendant linked macrocyclic chemistry was provided to understand the fundamentals of this area according to the lieratures. In chaper 2, synthesis dye linked macrocycles are described.We were attempt to dye linked S2O2 mixed donor macrocycles begin N,N'-phenyl diethanol amine. As process make compound 13 is easy comparatively, was neted by high yield. Compound 13 sythesis progressed reaction by in situ because separation is impossible. Got dibenzodialdehyde 10, 11, 12reacting salicylaldehyde and dibromomthane, dibromoethane and dibromopropane mixing solvent of water and methanol, and make compounds 7, 8, 9 because done this to do reduction using sodium borohydride, and got dibenzodichloride 4, 5, 6 used thionyl chloride under dichloromethane solvent. The cyclization reaction of 4, 5, 6 with 13 in the presence of Cs_(2)CO_(3)gave crystalline compounds 1, 2, 3 Subsequently, the diazonium salt obtained from the reaction of p-nitroaniline with NaNO_(2) was in situ added to a solution of 1, 2, 3 providing the desired products 1, 2, 3 as red powder. In chapter 3. UV-Vis spectrum study and crystal structure of mercury ion complex with dye linked macrocycles are described. The metal induced maxshift experiments shows Hg(II) ion was mostly selective to give the largest hypochromical shift, implying that the Hg(II) ion is the most suitable for L^(1), L^(2), L^(3). However there were no changes of band shift except Ag(I), Cu(II), Fe(III)and Al(III). When L^(1), L^(2), L^(3) was titrated with Hg(NO_(3))_(2) (0-5equiv) the equilibrium moved from L^(1), L^(2), L^(3)(λ_(max) = ∼480nm) to its 1:1 Hg(II) complex (λ_(max) = ∼364 nm) gradually showing the isosbestic point at ∼ 402 nm. During the course of elucidating the metal cation effect on the chromogenic behavior, an anion effect was unexpectedly observed. Surprisingly the maximum shift for the Hg(II) was acceptable only for non- or less-coordinating anions, such as NO_(3)^(-) (Δλ=130 nm) and ClO_(4)^(-) (Δλ=140 nm). In cases of Cl^(-) and SCN^(-), however, there were no changes upon complexation. This behavior could be explained the anion coordination to Hg(II) that occurs instead of nitrogen donor gave non-chromogenity. We suggested chromogenic switching system.