Department of Chemistry and Biochemistry, University of California, Los Angeles, 607 Charles E. Young Drive East, Los Angeles, California 90095, USA.
J Am Chem Soc. 2011 Jul 13;133(27):10410-3. doi: 10.1021/ja204304f. Epub 2011 Jun 21.
The synthesis and characterization of the first scandium arene inverted-sandwich complexes supported by a ferrocene diamide ligand (NN(fc)) are reported. Through the use of (NN(fc))ScI(THF)(2) as a precursor and potassium graphite (KC(8)) as a reducing agent, the naphthalene and anthracene complexes (NN(fc))Sc(μ-C(10)H(8)) and (NN(fc))Sc(μ-C(14)H(10)), respectively, were synthesized and isolated in moderate to high yields. Both molecular structures feature an inverted-sandwich geometry and exhibit short Fe-Sc distances. DFT calculations were employed to gain understanding of the electronic structures of these new scandium arene complexes. A variable-temperature NMR spectroscopic study of (NN(fc))Sc(μ-C(14)H(10)) indicated that two different structures are accessible in solution. Reactivity studies showed that the naphthalene complex (NN(fc))Sc(μ-C(10)H(8)) can be converted to the corresponding anthracene species (NN(fc))Sc(μ-C(14)H(10)) and that (NN(fc))Sc(μ-C(10)H(8)) can act as either a reductant or a proton acceptor. The reaction of (NN(fc))Sc(μ-C(10)H(8)) with excess pyridine led to a rare example of C-C bond formation between two pyridine rings at the para position.
报告了首例由二茂铁二酰胺配体（NN(fc)）支持的钪芳烃反夹心配合物的合成与表征。通过使用（NN(fc))ScI(THF)(2)作为前体和钾石墨（KC(8)）作为还原剂，分别以中等至高产率合成并分离出萘和蒽配合物(NN(fc))Sc(μ-C(10)H(8))和(NN(fc))Sc(μ-C(14)H(10))。这两种分子结构均具有反夹心几何形状，并表现出较短的 Fe-Sc 距离。DFT 计算用于深入了解这些新型钪芳烃配合物的电子结构。(NN(fc))Sc(μ-C(14)H(10))的变温 NMR 光谱研究表明，在溶液中可以获得两种不同的结构。反应性研究表明，萘配合物(NN(fc))Sc(μ-C(10)H(8))可以转化为相应的蒽配合物(NN(fc))Sc(μ-C(14)H(10))，并且(NN(fc))Sc(μ-C(10)H(8))可以作为还原剂或质子接受体。(NN(fc))Sc(μ-C(10)H(8))与过量吡啶的反应导致了两个吡啶环在对位形成 C-C 键的罕见实例。
