Dicarbonyl compounds Iron carbonyl

Jiang S, Agoston GE, Chen T, Cabal M-P, Turns E (1995) BF3 Et20-promoted allylation reactions of allyl(cyclopentadienyl)iron(II) dicarbonyl complexes with carbonyl compounds. Organometallics 14 4697 -709... 

It should be noticed that iron complexes produce mostly monocarbonyl compounds, while nickel complexes give dicarbonyl compounds. The difference between nickel and iron was explained by the structures of the mononuclear iron complex and the dinuclear nickel complex formed by the reactions of the metal carbonyls with phenyl lithium as shown below 92>. 

Methylcyclopentadiene readily undergoes reaction with metal carbonyls 47) and even 1,3-diphenylcyclopentadiene reacts with iron carbonyl 4S). A novel method for obtaining a ferrocene with one substituted ring, is the reaction of 1,3-diphenylcyclopentadiene with the dimer of cyclopentadienyl-iron dicarbonyl at 170° C to produce 1,3-diphenylferrocene in 15% yield. Other substituted cyclopentadienes which have been used are tetraphenyl-cyclopentadienone in the preparation of tetraphenyl(hydroxy)cyclopenta-dienylmanganese tricarbonyl 49) and indene in the preparation of the dimer of indenylmolybdenum tricarbonyl (50). A variety of substituted fulvenes have been used in the preparation of substituted cyclopentadienyl metal tricarbonyl compounds of Cr, Mo, and W (57, 52). This latter reaction proceeds best in the presence of a solvent, such as 1,2-dimethoxyethane, to permit easy abstraction of hydrogen. 

Ti -Allyl(dicarbonyl)(nitrosyl)iron complexes can also be reacted with electrophiles. Subjection to a,P-unsaturated carbonyl compounds leads to 5,E-unsaturated carbonyl compounds (Scheme 4-91). For this transformation, the allyliron complexes can even be generated in situ from haloalkenes and TBAFe. ... 

In a similar manner, Jt-allyl complexes of manganese, iron, and molybdenum carbonyls have been obtained from the corresponding metal carbonyl halides [5], In the case of the reaction of dicarbonyl(r 5-cyclopentadienyl)molybdenum bromide with allyl bromide, the c-allyl derivative is obtained in 75% yield in dichloromethane, but the Jt-allyl complex is the sole product (95%), when the reaction is conducted in a watenbenzene two-phase system. Similar solvent effects are observed in the corresponding reaction of the iron compound. As with the cobalt tetracarbonyl anion, it is... 

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