Synthesis, characterization and reactivity of iron–olefin complexes of the type [CpFe(CO)2(η2-CH2CHR)]+X− (Cp=η5-C5H5; R=CH3 to n-C14H29; X=PF6 or BF4)

A series of iron–olefin complexes of the type [CpFe(CO)2(η2-CH2CHR)]+ (R=CH3 to n-C14H29) have been prepared using various synthesis methods. In addition, the complexes [Cp*Fe(CO)2(η2-CH2CHR)]+ (Cp*=η5-C5(CH3)5; R=CH3, n-C3H7 and n-C14H29) and [CpRu(CO)2(η2-CH2CHR)]+ (R=CH3, n-C3H7 and n-C14H29) have been synthesized by reacting the iron–alkyl complexes Cp*Fe(CO)2(CH2CH2R) or ruthenium–alkyl complexes CpRu(CO)2(CH2CH2R) with Ph3CPF6. A number of these complexes are new and have been fully characterized by analytical and spectroscopic methods. The reaction of [CpFe(CO)2(η2-CH2CHR)]+ with the isopropoxide ion gave the new ether derivatives [CpFe(CO)2(CH2CH{OCH(CH3)2}R)] (R=CH3, n-C2H5, n-C4H9 and n-C13H27).