Effect of a Tridentate Ligand on the Structure, Electronic Structure, and Reactivity of the Copper(I) Nitrite Complex: Role of the Conserved Three-Histidine Ligand Environment of the Type-2 Copper Site in Copper-Containing Nitrite Reductases
作者:Masato Kujime、Chiemi Izumi、Masaaki Tomura、Masahiko Hada、Hiroshi Fujii
DOI:10.1021/ja075575b
日期:2008.5.1
It is postulated that the copper(I) nitrite complex is a key reaction intermediate of copper containing nitrite reductases (Cu-NiRs), which catalyze the reduction of nitrite to nitric oxide (NO) gas in bacterial denitrification. To investigate the structure-function relationship of Cu-NiR, we prepared five new copper(I) nitrite complexes with sterically hindered tris(4-imidazolyl)carbinols [Et-TIC
据推测,亚硝酸铜 (I) 复合物是含铜亚硝酸盐还原酶 (Cu-NiRs) 的关键反应中间体,可在细菌反硝化过程中催化亚硝酸盐还原为一氧化氮 (NO) 气体。为了研究 Cu-NiR 的结构-功能关系,我们制备了五种具有空间位阻三(4-咪唑基)甲醇 [Et-TIC = tris(1-methyl-2-ethyl-4-imidazolyl) )甲醇和 iPr-TIC = 三(1-甲基-2-异丙基-4-咪唑基)甲醇]或三(1-吡唑基)甲烷[Me-TPM = 三(3,5-二甲基-1-吡唑基)甲烷;Et-TPM = 三(3,5-二乙基-1-吡唑基)甲烷;和 iPr-TPM = 三(3,5-二异丙基-1-吡唑基)甲烷]。所有这些亚硝酸铜 (I) 配合物的 X 射线晶体结构都是单核 eta(1)-N 结合亚硝酸盐配合物,具有扭曲的四面体几何形状。通过吸收、磁圆二色性 (MCD)、核磁共振和振动光谱研究了配合物的电子结构。所有这些配合物都是