Reactions of acylferrate anion [CH3COFe(CO)4]− with methyl methyl iodide and acetylenes. Synthesis of mono- and dinuclear alkenyl ketone iron complexes. X-ray structure of [NEt4][IFe(CO)3(COCPh)2)]

Collmanʹs reagent [NEt4][CH3COFe(CO)4] (1) reacts with a half equivalent of methyl iodide and diphenylacetylene in acetone at 25 °C for 10 min to give [NEt4][Fe2(CO)6(μ2-CPhCPhCOCH3)] (2). When the reaction of [NEt4][CH3COFe(CO)4] (1) was carried out with an excess of methyl iodide a mixture of [NEt4][IFe(CO)3(C(O)CPh)2] (3) and [Fe2(CO)6{μ-CPhCPhCCH3(OCH3)}] (4) complexes were obtained. Complex 3 was characterized by X-ray analyses.