期刊
INORGANIC CHEMISTRY
卷 60, 期 9, 页码 6712-6720出版社
AMER CHEMICAL SOC
DOI: 10.1021/acs.inorgchem.1c00539
关键词
-
资金
- US National Science Foundation [CHE-1565501, CHE-0840444]
The treatment of Fe{N(SiMe3)(2)}(2) with phenol or thiol yields various compounds with different structures and properties in moderate to excellent yields. The behavior of different complexes towards ammonia coordination and ammonia release is discussed, providing insights into the potential behavior of the proposed iron-sulfur active site in nitrogenases.
Treatment of Fe{N(SiMe3)(2)}(2) with 2 equiv of the appropriate phenol or thiol affords the dimers {Fe(OC6H2-2,6-Bu(2)(t)4-Me)(2)}(2) (1) and {Fe(OC6H3-2,6-Bu-2(t))(2)}(2) (2) or the monomeric Fe{SC6H3-2,6-(C6H3-2,6-Pr-2(i))(2)}(2) (3) in moderate to excellent yields. Recrystallization of 1 and 2 from diethyl ether gives the corresponding three-coordinate ether complexes Fe(OC6H3-2,6-Bu-2(t)-4-Me)(2)(OEt2) (4) and Fe(OC6H3-2,6-Bu-2(t))2(OEt2) (5). In contrast, no diethyl ether complex is formed by the dithiolate 3. The H-1 NMR spectra of 4 and 5 show equilibria between the ether complexes and the base-free dimers. A comparison of these spectra with those of the dimeric 1 and 2 allows an unambiguous assignment of the paramagnetically shifted signals. Treatment of 1 with excess ammonia gives the tetrahedral diammine Fe(OC6H2-2,6-Bu-2(t)-4-Me)(2)(NH3)(2) (6). Ammonia is strongly coordinated in 6, with no apparent loss of ammine ligand either in solution or upon heating under low pressure. In contrast, significantly weaker ammonia coordination is observed when dithiolate 3 is treated with excess ammonia, which gives the diammine Fe{SC6H3-2,6-(2,6Pr(2)(i)-C6H3)(2)}(2)(NH3)(2) (7). Complex 7 readily loses ammonia either in solution or under reduced pressure to give the monoammine complex Fe{SC6H3-2,6-(2,6-Pr-2(i)-C6H3)(2)}(2)(NH3) (8). The weak binding of ammonia by iron thiolate 7 reflects the likely behavior of the proposed iron-sulfur active site in nitrogenases, where release of ammonia is required to close the catalytic cycle.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据