A study of the reaction between phenyl substituted cyclopentadiene and iron pentacarbonyl: the unusual structure of π-complex (η4-C5Ph4H2)Fe(CO)3

The reaction of a series of phenyl substituted cyclopentadienes C5PhnH6−n (n=1–4) and iron pentacarbonyls in refluxing toluene was studied. The corresponding diiron complexes [(η5-C5PhnH6−n)Fe(CO)]2(μ-CO)2 (n=1–4) and phenyl substituted ferrocenes (η5-C5PhnH6−n)2Fe (n=3,4) were obtained. The reaction of tetraphenylcyclopentadiene and iron pentacarbonyl in refluxing toluene also led to the formation of π-complex (η4-C5Ph4H2)Fe(CO)3 (1), which exhibited exceptional air and thermal stabilities. The molecular structure of 1 has been determined by X-ray diffraction and an unusual rearrangement of a phenyl group was found.