偶氮金屬配位化合物合成鑑定與性質探討;Synthesis and Property of Metal Azo Compounds

Please use this identifier to cite or link to this item: http://ir.lib.ncu.edu.tw/handle/987654321/71337

Title:	偶氮金屬配位化合物合成鑑定與性質探討;Synthesis and Property of Metal Azo Compounds
Authors:	羅偉中;Luo,Wei-Zhong
Contributors:	化學學系
Keywords:	偶氮;微流體
Date:	2016-07-26
Issue Date:	2016-10-13 12:45:20 (UTC+8)
Publisher:	國立中央大學
Abstract:	閃化學(flash chemistry)的有機合成，是指不穩定的中間物質，僅能短時間存活，反應過程只需要一秒或更短的時間，無法使用常規的批次反應達成。但在微流體反應系統中，比表面積大幅增加，熱傳及質傳快速，能使反應快速的進行，故閃化學反應在微流體反應器中卻非常適合。簡單調整實驗參數，便可使有機合成反應在微流體反應器中得到理想的效果。本論文中利用微流體反應之系統合成4個偶氮化合物並使之金屬化。 4個偶氮化合物的UV-Vis光譜中，呈現出明顯的π→π峯訊和n→π 峯訊。而偶氮化合物金屬化後，UV-Vis光譜中發現π→π躍遷兩個峯訊僅有輕微的位移和峯訊強度的變化，其他大致相同，但n→π峯訊因為金屬與配體鍵結的關係，產生紅移現象。鉻(Cr3+)金屬偶氮配體化合物的ESI質譜分析，發現其中心Cr3+離子在ESI過程中會還原成Cr2+。Cr2+水溶液離子交換速率比Na+水溶液離子交換速率大約快2倍，游離化過程中產生陽離子交換，在質譜圖中看到M及M-25的峯訊。;A flash reaction in organic chemistry is a reaction, in which an unstable intermediate is with very short life and the reaction is completed in one second or less. Consequently it is very difficult to conduct such a reaction in common batch type setups to successfully obtain the end product. On the other hand, a microfluidic reactor system exhibits very large specific area in setup and has very great mass transfer and heat transfer property. A microfluidic reactor allows fast heating or cooling, and thus is suitable for a flash reaction and in general favoring rapid reactions. One could achieve very good results to run organic reactions in microfluidic reactors by simple adjustment of experimental parameters. In this thesis, the preparation of 4 azobenzene derivatives was successfully demonstrated using the microfluidic reactor system. The azobenzenes were used as chelates to coordinate to chromium and iron to form metallic azo-dyes. The 4 azobenzenes and 8 metallic azo-dyes were studied with the UV-Vis spectroscopic method. As ligands, the azobenzenes show clear π−π* and n−π* absorption bands, while the metallic azo-dyes show slight shift/change on π−π* absorption bands yet pronounced red-shifts on n−π* absorption bands. The 4 azobenzenes and 8 metallic azo-dyes were all analyzed with mass spectroscopic method using the electrospray ionization source. The Cr+3 azo-dyes were interesting in that the central Cr+3 metal ions along the ESI process could be reduced to Cr+2 metal ions that led to exchange of Cr+2 metal ions with the counter Na+ metal ions. The negative mass spectra of Cr+3 azo-dyes revealed very strong peaks at m/e = [M] and [M-25], where M is the molecular ion, agreeing to the facile water exchange rates for Cr+2 and Na+ but inert water exchange for Cr+3. No such exchange was observed for the analogous Fe+3 azo-dyes: slow water exchange being known for both Fe+3 and Fe+2 metal ions.
Appears in Collections:	[Graduate Institute of Chemistry] Electronic Thesis & Dissertation

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