Studies on polyhalides. 31 - On 1,1 '-dimethylferriciniumpolyiodides [(MeH4C5)(2)Fe]I-x with x=3, 5: Preparation and crystal structures of a triiodide (diMeFc)I-3 and a pentaiodide (diMeFc)I-5 [German]

摘要

Dimethylferrocene (diMeFc) may be oxidized by iodine analogous to ferrocene (Fc) and decamethylferrocene (DMFc) to the dimethylferrocenium ion (diMeFc)(+) and precipitated as crystalline solids dimethylferrocenium triiodide (diMeFc)I-3, dimethylferrocenium pentaiodide (diMeFc)I-5 and dimethylferrocenium heptaiodide (diMeFc)I-7. The two compounds with higher iodine content are new The first two compounds are characterized by X-ray diffraction methods on single crystals. The structures are built up from complex cations with ecliptic conformation and isolated triiodide ions or remarkably concatenated pentaiodide ions. Dimethylferrocenium triiodide C12H14FeI3 crystallizes triclinically in P (1) over bar with a=743.3(2) pm, b=796.8(2) pm, c=1471.7(4) pm, alpha=98.53(2)degrees, beta=97.30(2)degrees, gamma=109.50 degrees and Z=2. The already known simple crystal structure may now be described without disordered anions. Dimethylferrocenium pentaiodide C12H14FeI5 crystallizes orthorhombically in Pnna with a=1807.7(6) pm, b=1543.4(10) pm, c=1413.0(11) pm and Z=8. The crystal structure contains pentaiodide chains (1)(infinity)[I-3(-). I-2] with alternating planar and helical regions. [References: 27]