Electrophilic attack on the [µ3-acetyl-C1(Fe1 : Fe2)O(Fe1 : Fe3)]nonacarbonyl-triangulo-triferrate(1–) anion by fluoroboric acid and methyl fluorosulphate. Carbon–oxygen bond cleavage to give µ3-ethylidyne and µ-methoxo-groups. X-Ray crystal structures of Fe3(CO)9(µ3-MeCO)(µ-H), Fe3(CO)9(µ3-CMe)(µ3-OMe), and Fe3(CO)9(µ3-CMe)(µ3-COMe)

Abstract

The (µ₃-acetyl)-nonacarbonyltriferrate(1–) ion, [Fe₃(CO)₉(µ3-MeCO)]^–, reacts with fluoroboric acid to give the neutral clusters Fe₃(CO)₉(µ₃-MeCO)(µ-H)(1), Fe₃(CO)₁₀(µ-CMe)(µ-H)(2), and in small yield, Fe₃(CO)₉(µ₃-MeCOH)(3). With methyl fluorosulphate the anion reacts to give either Fe₃(CO)₉(µ₃-CMe)(µ₃-OMe)(4) or Fe₃(CO)₉(µ₃-CMe)(µ₃-COMe)(5), depending upon the reaction conditions. The crystal structures of (1), (4), and (5) have been determined by X-ray diffraction studies. Mechanisms for the electrophilic attacks and for the C–O bond cleavage of the µ₃-acetyl group are discussed.