Diiron Bridged-Thiolate Complexes That Bind N2 at the FeIIFeII, FeIIFeI, and FeIFeI Redox States
Diiron Bridged-Thiolate Complexes That Bind N2 at the FeIIFeII, FeIIFeI, and FeIFeI Redox States
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DOI：
10.1021/jacs.5b04738
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发表时间：
2015-06-17
影响因子：
15
通讯作者：
Peters, Jonas C.
中科院分区：
文献类型：
--
作者：
Creutz, Sidney E.;Peters, Jonas C.
所有已知的固氮酶辅因子都富含硫和铁，并被认为能够结合和还原N-2。尽管如此，结合N-2并且还具有硫供体配体的过渡金属模型络合物的合成实例仍然很少。我们在此报告了一系列不寻常的低价二铁配合物具有硫醇盐和二氮配体。引入了一种新的双核配体支架，其支持Fe（mu-SAr）Fe二铁亚基，所述Fe（mu-SAr）Fe二铁亚基在至少三种氧化态（（FeFeII）-Fe-II、（FeFeI）-Fe-II和（FeFeI）-Fe-I）上与二氮（N-2-Fe（mu-SAr）Fe-N-2）配位。（N-2-Fe（mu-SAr）Fe-N-2）体系经历结合的N-2的还原以产生NH3（类似于50%产率），并且可以有效地催化N2 H4还原成NH3和N-2。本发明的支架还支持与作为共配体的氢化物伴随的二氮结合。这些类型的合成模型复合物是理想的，以最终约束有关铁介导的固氮在合成和生物系统的假设。
All known nitrogenase cofactors are rich in both sulfur and iron and are presumed capable of binding and reducing N-2. Nonetheless, synthetic examples of transition metal model complexes that bind N-2 and also feature sulfur donor ligands remain scarce. We report herein an unusual series of low-valent diiron complexes featuring thiolate and dinitrogen ligands. A new binucleating ligand scaffold is introduced that supports an Fe(mu-SAr)Fe diiron subunit that coordinates dinitrogen (N-2-Fe(mu-SAr)Fe-N-2) across at least three oxidation states ((FeFeII)-Fe-II, (FeFeI)-Fe-II, and (FeFeI)-Fe-I). The (N-2-Fe(mu-SAr)Fe-N-2) system undergoes reduction of the bound N-2 to produce NH3 (similar to 50% yield) and can efficiently catalyze the disproportionation of N2H4 to NH3 and N-2. The present scaffold also supports dinitrogen binding concomitant with hydride as a co-ligand. Synthetic model complexes of these types are desirable to ultimately constrain hypotheses regarding Fe-mediated nitrogen fixation in synthetic and biological systems.