Cyclopentadienyliron dicarbonyl dimer

In a more complex type of reaction, propene reacts with methyl trichloro-acetate under the catalytic influence of cyclopentadienylmolybdenum tricarbonyl or cyclopentadienyliron dicarbonyl dimers to give 4-methyl-2,2 -... 

Exposure of the Baylis-Hillman adduct 178 to a high-pressure carbon monoxide atmosphere in the presence of a cyclopentadienyliron dicarbonyl dimer (Fp2) catalyst unexpectedly gives small quantities of the A -formylindoline and indolecarboxylate (Equation 114) <2003T747>. 

The 77-cyclopentadienyliron dicarbonyl dimer and the mixed metal carbonyl 7r-cyclopentadienyliron-manganese heptacarbonyl are protonated by strong acids to form isolatable salts, namely [CpFe(CO)2]2H +PF6 and [CpFeMn(CO)7H]+PF6 . The ruthenium dimer [CpRu(CO)2]2 behaves similarly, although no salt was isolated (63). 

Cyclopentadienyliron dicarbonyl dimer Iron, tetracarbonylbis (11 -2,4-cyclopentadien-... 

Cyclooctadlene (111-78-4), 70, 169 Cyclopentadienyliron dicarbonyl dimer, 70, 177 Cyclopentadienyllron dicarbonyl dimethsulfonium tetrafluoroborate ... 

Into a dry, one-necked, 2000-mL, round-bottomed flask is placed a mediumsized magnetic stirring bar (Note 1) and cyclopentadienyliron dicarbonyl dimer [CsH5(CO)2Fe]2, (0.50 mol equiv, 0.21 mol, 74.4 g Notes 2 and 3). Sodium dispersion (40% by weight) in light mineral oil (1.25 mol equiv, 0.52 mol, 30.1 g Notes... 

To a solution of 2.45 g (6.92 mmol) of cyclopentadienyliron dicarbonyl dimer in 15 mL of anhyd THE are added 6.50 g (17.0 mmol) of 6% Na/Hg. The mixture is stirred vigorously at 25 rC for 2 h. During this period, the colour oT the solution changes from dark brown to deep red. The mixture is then cooled to... 

Cyclopentadienyliron dicarbonyl dimer [C5Hs(CO)2Fe]2 can be purchased from Alfa Products, Morton/Thiokol Inc. or Aldrich Chemical Company, Inc. Alternatively, it is easily and inexpensively prepared by heating dicyclopentadiene with iron pentacarbonyl. Our yield (80-90%) of this reagent is considerably higher than that reported in the literature procedure.2... 

Cyclopentadienyliron dicarbonyl dimer Iron, tetracarbonylbis (ri5-2,4-cyclopentadien-1 -yl)di-, (Fe-Fe) (9) (38117-54-3)... 

The only practical preparations of cyclopentadienyliron dicarbonyl dimer involve reactions of iron pentacarbonyl with either cyclopentadiene or its dimer at elevated temperatures. Although the use of monomeric cyclo-pentadiene is reported to give a higher yield and possibly a purer product, use of an autoclave is required because of the low boiling point of cyclopentadiene if a reasonable amount of product is to be prepared. For this reason the reaction between iron pentacarbonyl and dicyclopentadiene may well be more convenient since it can be carried out in an open system. The preparation described below involves dicyclopentadiene. 

If several preparations of cyclopentadienyliron dicarbonyl dimer are contemplated, it is desirable to retain the dicyclopentadiene filtrate (but not the pentane washings) the filtrate should be kept under nitrogen, and about 50 or 100 ml. of fresh dicyclopentadiene should be added for the next preparation. Besides being more economical in terms of dicyclopentadiene consumed, this technique may raise the yield of product from 40 to 60-70%. 

In order to convert cyclopentadienyliron dicarbonyl dimer to cyclopentadienyliron dicarbonyl iodide, it is treated with iodine in chloroform. ... 

A mixture of 50 g. (0.141 mol) of cyclopentadienyliron dicarbonyl dimer, 50 g. (0.197 mol) of iodine, and 250 ml. of chloroform is refluxed in a 500-ml. flask for about 30 minutes, an inert atmosphere being unnecessary. After cooling to room temperature, the mixture is washed in several portions in a separatory funnel with a solution of 100 g. of... 

Cyclopentadienyliron dicarbonyl dimer is a red-violet crystalline solid, sparingly soluble in pentane, but more soluble in polar organic solvents. It is fairly air-stable in the solid state, although solutions are slowly oxidized to iron(III) oxide. It may be sublimed at 110° at 0.1 mm., but extensive decomposition usually occurs. It reacts with dilute sodium amalgam to produce the sodium derivative, C6H6Fe(CO)2Na, which may be used to prepare a variety of derivatives. 

Cyclopentadienyliron dicarbonyl iodide is a black crystalline solid, which resembles cyclopentadienyliron dicarbonyl dimer in its solubility and air stability. It sublimes at about 90° at 0.1 mm. It may be used to prepare a variety of organoiron compounds. ... 

Reaction of the cyclopentadienyliron dicarbonyl anion, readily prepared from commercially available cyclopentadienyliron dicarbonyl dimer and sodium amalgam, with epoxides gives olefin complexes (XXXI) in good yields. The olefin ligand can be liberated from the complex using iodide ion (Giering et aU 1972). The reaction occurs with net retention of configuration and was proposed to occur via intermediates XXIX and XXX. 

D. CYCLOPENTADEENYLIRON DICARBONYL DIMER AND CYCLOPENTADIENYLIRON DICARBONYL IODIDE... 

Tetraphenylcyclobutadienecobalt dicarbonyl bromide (XXXIX) undergoes a number of reactions in which the cyclobutadiene-cobalt bond remains intact. Thus with cyclopentadienyliron dicarbonyl bromide (or the dimer) ligand transfer again occurred to give (cyclopentadienyl)(tetraphenyl-cyclobutadiene)cobalt (XXVIII) 64, 65). 

The first step is a simple displacement of two molecules of carbon monoxide. In the second step the acidic hydrogen of 7r-bonded cyclopentadiene shifts to the iron atom to give w-cyclopentadienyliron dicarbonyl hydride, a known compound. Two molecules of this iron hydride then add hydrogen to cyclopentadiene to form cyclopentene and the dimer of w-cyclopentadienyl-iron dicarbonyl. This reaction proceeds at temperatures between 150° and 220° C. Above 220° C, the remaining carbon monoxide molecules are displaced by a second molecule of cyclopentadiene forming ferrocene [42). 

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