Weiss Daniel T, Altmann Philipp J, Haslinger Stefan, Jandl Christian, Pöthig Alexander, Cokoja Mirza, Kühn Fritz E
Chair of Inorganic Chemistry/Molecular Catalysis, Department of Chemistry, Catalysis Research Center, Technische Universität München, Lichtenbergstr. 4, D-85747 Garching bei München, Germany.
Dalton Trans. 2015 Nov 14;44(42):18329-39. doi: 10.1039/c5dt02386f. Epub 2015 Jul 28.
The synthesis of copper, gold, nickel, palladium, platinum, and iron complexes with open chain tetra-N-heterocyclic carbene (NHC) ligands via transmetalation using silver NHC complexes is presented. The obtained complexes show differing coordination geometries depending on both ligand structure and metal. While the complexes of the coinage metals form di- or tetranuclear structures, the group 10 metal complexes exhibit a distorted square planar coordination geometry at the metal centers. In the case of iron an enhanced flexibility of the ligand - caused by a longer alkyl bridge - leads to octahedral complexes with a sawhorse-type coordination by the tetracarbene ligand and two cis acetonitrile ligands. To the best of our knowledge, this is the first known example of a tetracarbene ligand in sawhorse-type coordination within an octahedral coordination sphere. The remaining cis-labile sites are prone to exchange reactions as shown by addition of trimethylphosphine.
介绍了通过使用银氮杂环卡宾（NHC）配合物进行金属转移反应，合成具有开链四氮杂环卡宾（NHC）配体的铜、金、镍、钯、铂和铁配合物。所得到的配合物根据配体结构和金属的不同呈现出不同的配位几何构型。虽然贵金属的配合物形成双核或四核结构，但第10族金属配合物在金属中心呈现出扭曲的平面正方形配位几何构型。就铁而言，由较长烷基桥引起的配体更大的灵活性导致八面体配合物，其中四卡宾配体和两个顺式乙腈配体以交错式配位。据我们所知，这是八面体配位球内交错式配位的四卡宾配体的首个已知实例。如添加三甲基膦所示，其余的顺式不稳定位点易于发生交换反应。
