Inhaltszusammenfassung

While attempts to stack the nido clusters (mu-3-RP)(mu-3-S)Fe3(CO)9, 2, in a direct way to the closo compounds (mu-4-RP)(mu-4-S)Fe4(CO)11, 4, have been unsuccessful so far, the carbene substituted derivatives of 2 (mu-3-RP)(mu-3-S)Fe3(CO)8(CRR'), 1, react with Fe2(CO)9 to give the closo clusters 4 and their carbene derivatives (mu-4-RP)(mu-4-S)Fe4(CO)10(CRR'), 3, in fair yields. The carbene ligand of 1 obviously makes it considerably easier to introduce an Fe(CO)2 capping group. Cyclovoltamme...While attempts to stack the nido clusters (mu-3-RP)(mu-3-S)Fe3(CO)9, 2, in a direct way to the closo compounds (mu-4-RP)(mu-4-S)Fe4(CO)11, 4, have been unsuccessful so far, the carbene substituted derivatives of 2 (mu-3-RP)(mu-3-S)Fe3(CO)8(CRR'), 1, react with Fe2(CO)9 to give the closo clusters 4 and their carbene derivatives (mu-4-RP)(mu-4-S)Fe4(CO)10(CRR'), 3, in fair yields. The carbene ligand of 1 obviously makes it considerably easier to introduce an Fe(CO)2 capping group. Cyclovoltammetric analysis of the nido/closo pairs of compounds 1/3 and 2/4 respectively demonstrates that one electron reduction of the nido complexes requests a potential which is about 0.5 V more negative than the potential necessary for the corresponding reduction of the respective closo compounds. The observed sequence of reduction potentials corresponds to the predictions which may be derived from a model in which nido and closo compounds are considered as derivatives of organometallic pi-systems. All results are documented by the conventional analytical and spectroscopic techniques and in addition by two X-ray structure analyses. » weiterlesen» einklappen

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