Besmer Manuel Luca, Braband Henrik, Schneider Sven, Spingler Bernhard, Alberto Roger
Department of Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland.
Institute for Inorganic Chemistry, Georg-August-University Göttingen, Tammannstrasse 4, DE-37077 Göttingen, Germany.
Inorg Chem. 2021 May 3;60(9):6696-6701. doi: 10.1021/acs.inorgchem.1c00503. Epub 2021 Apr 13.
Dinitrogen (N) complexes of technetium (Tc) are rare, and only two examples have been reported. To complement this important class of complexes also for Tc, two different pincer-type complexes of Tc were studied to assess their abilities for coordinating dinitrogen. The reactions of the Tc complex [TcCl(PPh)(NCCH)] with the pincer ligands PNP and PNP respectively gave [Tc(PNP)Cl] and [Tc(PNP)Cl], the first structurally characterized Tc complexes with -coordinated pincer ligands. Reductions with [Co(Cp*)] under N gave the mononuclear bis-dinitrogen complex [Tc(PNP)(N)] and the dinuclear complex Tc(PNP)(N)Cl with both a bridging and a terminal N ligand. Spectroscopy and crystal structures confirm their identities. The complexes are stable under a dinitrogen atmosphere, and the N ligands are tightly bound. The results for the complexes with the PNP pincer allow a comparison to its rhenium homologue, which has recently been shown to split the N ligand with the formation of a nitrido complex.
锝（Tc）的二氮（N）配合物很罕见，仅报道过两个例子。为了补充这一重要类别的锝配合物，研究了两种不同的锝钳形配合物，以评估它们配位二氮的能力。锝配合物[TcCl(PPh)(NCCH)]与钳形配体PNP和PNP分别反应，得到了[Tc(PNP)Cl]和[Tc(PNP)Cl]，这是首批具有 - 配位钳形配体且结构已表征的锝配合物。在氮气氛围下用[Co(Cp*)]还原得到单核双二氮配合物[Tc(PNP)(N)]和双核配合物Tc(PNP)(N)Cl，后者同时含有一个桥连氮配体和一个端基氮配体。光谱学和晶体结构证实了它们的结构。这些配合物在二氮气氛下稳定，且氮配体结合紧密。含PNP钳形配体的配合物的结果可与铼同系物进行比较，最近已表明铼同系物可使氮配体裂解形成氮化物配合物。
