生化模擬亞硝酸鹽環原酶模型化合物與吡咯銅錯合物的合成

Synthesis and Spectroscopic Characterization of Model Complexes of Copper Nitrite Reductase

林依蓉(I-Jung Lin)

指導教授 ： 許智能

高雄醫學大學/生命科學院/醫藥暨應用化學研究所/碩士(2008年)

摘要

中文摘要
關於生物代謝脫硝過程之亞硝酸還原酶(CuNIR)之模擬，銅-亞硝酸錯合物為一類相當重要的模型化合物。CuNIR在分類上為一同型三聚體，具催化功能單元主要是座落在兩個單體之間的Type 2 銅中心。在氧化態的CuNIR中，Type 2 銅中心為四面體配位環境，周圍三個配位子為histidine，第四個配位子則是水分子。
在本論文中，成功的合成出一系列在結構上具有含氮三牙配位子及Cu(I)- NO2-的單核銅一價化合物；包括化合物[Cu(HC(3,5-Me2Pz)3)(NO2)] (1), [Cu(HC(3-tBuPz)3)(NO2)] (2), PPN[Cu(HB(3,5-Me2Pz)3)(NO2)] (3)及PPN[Cu(HB(3-tBuPz)3)(NO2)] (4)。這些化合物皆經紅外光譜，紫外可見光光譜及核磁共振光譜之鑑定。由紫外可見光光譜指出化合物(1)至(4)皆具有一明顯之吸收峰，推測為CuI→NO2- MLCT之特徵。其中化合物(1)及(3)亦經由X-ray單晶繞射解出其真實的分子固態結構。本論文化合物(1)至(4)的合成與鑑定可以提供對於銅一價含氮三牙配位子錯合物在不同的電荷環境、立體障礙下的研究與討論。為得知本論文所合成之化合物是否具亞硝酸還原功能性，化合物(1)及(3)與酸之反應也一並進行探討。

關鍵字

銅一價亞硝酸錯合物

並列摘要

Abstract
Copper-nitrite complexes are applicable to the copper nitrite reductase (CuNIR) class of enzymes that are part of the biological denitrification process. These enzymes are homotrimers where the catalytically active type 2 centers are located at each of the interfaces of two subunits of the enzyme. In the oxidized form, the type 2 centers are tetrahedrally coordinated by three histidines and a water molecule.
In this work, we have synthesized a series of novel complexes containing the Cu(I)-NO2- unit and tridenated ligand of N-donor. The mononuclear complexes [Cu(HC(3,5-Me2Pz)3)(NO2)] (1), [Cu(HC(3-tBuPz)3)(NO2)] (2), PPN[Cu(HB(3,5-Me2Pz)3)(NO2)] (3) and PPN[Cu(HB(3-tBuPz)3)(NO2)] (4) have been synthesized and characterized by FTIR, UV-Vis and NMR spectroscopies in solution. These complexes exhibit an intense electronic absorption feature that was assigned as a CuI→NO2- MLCT transtion on the basis of UV-Vis results. The complex (1) and (3) also investigated via single crystal X-ray diffraction to comfirm their solid state structure. The synthesis and characterization of those compounds have provided fundamental knowledge about copper(I) complexes containing nitrite donor ligand and different scorpionate ligands, which were also have implications for environmental influences on similar species in biological and catalytic systems.Investigations of complex (1) and (3) with acid (CF3COOH) were also performed to probe the viability of the complexes as funtional NIR models.

並列關鍵字

Copper Nitrite complex

參考文獻

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