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Sünkel, Karlheinz and Hofmann, Julian (1993): Koordinationschemie Perhalogenierter Cyclopentadine und Alkine, XV. Systematischer Aufbau von fünffach ringsilylierten Cyclopentadienyl-mangan-Komplexen aus [C5Br5]Mn(CO)3. Molekülstruktur von [C5Br3(SiMe3)2]Mn(CO)3. In: Chemische Berichte, Vol. 126, No. 8: pp. 1791-1795
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Abstract

Coordination Chemistry of Perhalogenated Cyclopentadienes and Alkynes, XV[1]. - Systematic Generation of Fivefold Ring-Silylated Cyclopentadienyl Manganese Complexes from [C5Br5]Mn(CO)3. Molecular Structure of [C5Br3(SiMe3)2]Mn(CO)3 [C5Br5]Mn(CO)3 reacts in a sequence of alternate bromine-lithium exchange reactions and electrophilic silylations by SiMe3Cl or SiMe3OSO2CF3 to give [C5Br5-n(SiMe3)n]Mn(CO)3, where n = 1 (1), 2 (2), or 3 (3). A crystal structure determination of 2 shows the two silyl substituents in the relative 1,3-orientation. Addition of one or two equivalents of BuLi and SiMe2HCl to a solution of 3 yields [C5Br2-n(SiMe3)3-(SiMe2H)n]Mn(CO)3 with n = 1 (4) and 2 (5), respectively. If 1 is treated twice with 2 eq. of BuLi and then 2 eq. of SiMe2HCl, a further pentasilylated compound, [C5(SiMe3)(SiMe2H)4]-Mn(CO)3 (6), is obtained. In situ chlorination of [C5(SiMe2H)5]Mn(CO)3 or 6 with PdCl2, followed by addition of MeMgCl, yields after chromatography an inseparable mixture of [C5(SiMe3)4X]Mn(CO)3 compounds, where X = H (7a), SiMe2H (7b), and SiMe3 (7c).