Mono- versus bidentate coordination of the NONOate [Et2N(N2O2)]- to copper(II) complexes of tetradentate ligands
Mono- versus bidentate coordination of the NONOate [Et2N(N2O2)]- to copper(II) complexes of tetradentate ligands
复制标题
DOI：
10.1039/a800561c
复制
发表时间：
1998-05-01
影响因子：
3.3
通讯作者：
Tolman, WB
中科院分区：
文献类型：
--
作者：
Schneider, JL;Halfen, JA;Tolman, WB
合成了[Et2N(N2O2)](-)与四齿、1，4，7-三氮杂环烷与吡啶(L-Py)、酰胺(L-HAMH)或酚类(L-R2，R=Me，或Bu-t酚基取代基)组成的四齿、三脚架配体的铜(II)配合物。在L-Py和L-HAMH担载的配合物中观察到[Et2N(N2O2)](-)的双齿O，O配位，但L-R2中较强的酚性供体通过末端氧原子诱导了新的单齿配位，X-射线晶体学定义为R=Bu-t。比较[Et2N(N2O2)](-)在结合双齿时和结合单齿时的成键参数，发现N-O距离有细微但显著的差异。用化学发光法测定化合物中一氧化氮(NO)的释放量和释放速率。尽管不同配位方式导致[Et2N(N2O2)](-)结构参数不同，但NO的释放速率没有明显变化。
Copper(II) complexes of [Et2N(N2O2)](-) with tetradentate, tripodal ligands composed of 1,4,7-triazacyclononanes with pyridine (L-Py), amide (L-HAmH) Or phenolate (L-R2, R = Me, or Bu-t phenolate substituents) groups as the fourth donor were prepared and characterized by spectroscopic and X-ray crystallographic methods. Bidentate O,O-coordination of [Et2N(N2O2)](-) was observed in the complexes supported by L-Py and L-HAmH, but the stronger phenolate donor in L-R2 induced novel monodentate coordination via the terminal oxygen atom, defined by X-ray crystallography for R = Bu-t. Comparison of the bonding parameters of [Et2N(N2O2)](-) when bound bidentate vel sus when bound monodentate revealed subtle but significant differences in the N-O distances. The amount and rate of nitric oxide (NO) release from the compounds was measured using a chemiluminescence detection method. Despite the differences in [Et2N(N2O2)](-) structural parameters resulting from the divergent coordination modes, insignificant variation of the rates of NO release therefrom were found.