Dicarbonyl iron chloride

The starting materials for these complexes are dicarbonyl(cyclopentadienyl)-iron chloride (Fischer and Moser, 1970) and the dicarbonylcyclopentadienyl-iron anion [as the sodium salt (Green and Nagy. 1963)], both obtainable from tetracarbonyl (di-Tr-cyclopentadienyl)diiron which is available commercially. The reaction is carried out in tetrahydrofuran (THF). Equation (1) demonstrates the ease of manipulation of these substances in the preparation of an olefin complex from an epoxide. The tetrafluoroborate salt precipitates from ether. This reaction is also useful as a means of reducing expoxides stereospecifically to olefins with retention of configuration. The olefin is readily liberated from the complex by treatment with sodium iodide in acetone at room temperature for 15 min (Giering et ai, 1972). 

An experimental illustration of the GA is shown in Fig. 21. The molecule cyclopentadieny 1-iron-dicarbonyl-chloride was irradiated with pulses of 800 nm radiation that were initially 80 ns long before entering the pulse shaper. The phases of the laser pulses were modified with... 

For the preparation of unsymmetrical ferrocenes, two ways by which only mono-substituted derivatives are produced have been suggested. One route starts from iron tetracarbonyl and a substituted cyclopenta-diene the other from monocyclopentadienyl iron dicarbonyl bromide, which on treatment with a substituted cyclopentadienyl lithium is finally converted into the corresponding mono-substituted ferrocene. Experience shows the first method to be more suitable for the preparation of aryl, and the latter method for the preparation of alkyl, derivatives (57). Corresponding work already carried out on substitution in Ru(C5H6)2 and Os CsH5)2 has also been fruitful. It is found that in the Friedel-Crafts reaction with acetyl or benzoyl chloride there is a distinct predominance of mono- over disubstitution as the atomic weight of the central atom increases (47, 72). 

The preparation of dicarbonyl(T -cyclopentadienyl)(2-methyl-l-propenyl-KC )iron requires 3-chloro-2-methyl-l-propene (methailyl chloride), not the reagent given in Reference 1, p. 165. ... 

Michael reactions. 1,3-Dicarbonyl form with catalysis of iron(III) chloride h 46-100%). An intramolecular version i 7-membered ring. ... 

Palladium(ll)-catalyzed intramolecular stereoselective Irons alkoxycarbonylation of 4-alkyl- and 4-aryl-3-butyn-l-ols 7 gives /f-tetrasubstituted a-methylene-y-butyrolactones 8 if conducted in the presence of copper(II) chloride, methyloxirane and triethyl orthoacetate. In the absence of the copper salt, intramolecular dicarbonylation occurs (e.g., giving 9, see Section 1.5.8.3.3.). The latter reaction type is also observed if the alkyne moiety is substituted by a trimethylsilyl instead of an alkyl or aryl group60,61. 

Several preparations of dicarbonyl dinitrosyl iron have been reported including treatment of [Fe3(CO)i2] or [Fe2(CO)9] with nitric oxide, acidification of a mixture of [HFe(CO)4] and nitrite ion, reaction of iron pentacarbonyl with nitrosyl chloride and acidification of a mixture of [Fe(CO)3NO] and nitrite ion as in equations (2) and (3). 

The solution is cooled in an ice bath and is stirred rapidly as 9.65 g (0.107 mole) of l-chloro-2-methyl-l-propene (isobutenyl chloride) [Aldrich] is added over a period of 5 min. The reaction can be followed by observing the changes in the IR spectrum of the solution. The carbonyl absorption bands characteristic of the anion are replaced by those typical of the product at 1998 and 1950 cm. Upon completion of the addition of l-chloro-2-methyl-l-propene, stirring at 0" is continued for 1 hr to ensure completion of the reaction. The resulting solution of dicarbonyl (Ti -cyclopentadienyl)(2-methyl-l-propenyI-KC )iron may be used directly without purification. Alternatively, the product can be isolated and purified by removing solvent under reduced pressure, followed by chromatogra(>Ay of the residue on 300 g of neutral activity III alumina. The column is made up in anhydrous diethyl ether, and after dissolving the crude product in petroleum ether, elution under N2 is carried out with this solvent. The product may 6e further purified by short-path distillation at pressures less than 10 mm (pot temperature less than 40°). It is then sufficiently pure to be stored at -20° for... 

Initially, this field was pioneered by Li who reported in 2007 on the formation of new carbon-carbon bonds directly starting from diarylmethanes and 1,3-dicarbonyl compounds under mild reaction conditions (80-100 °C, 5-36 h) in the presence of catalytic quantities of an inexpensive iron precursor (iron(ii) chloride, 20 mol%) and stoichiometric quantities of an oxidant (DTBP). The overall reaction can be regarded as an iron(ii) chloride-catalysed oxidative activation of a benzylic carbon-hydrogen bond followed by a cross-coupling reaction to form a carbon-carbon bond (Scheme 13.7, bottom). The mechanistic proposal is based on a single-electron transfer pathway as shown in Scheme 13.7. Initial homolysis of DTBP in the presence of the iron(ii) salt forms both tert-butoxyl radical and an iron(iii) species. Then, proton abstraction from the diarenemethane generates the two key... 

Cl4H20CIC0NBO3S2, Bis(pyridinealdehydethiosemicarbazonato)cobalt-(III) chloride trihydrate, 40B, 847 Cl i H2oFeN202Sii, Bis-(cyclopentamethylenedithiocarbamato)iron(lI) dicarbonyl, 38B, 858... 

Dicarbonyl(cyclopentadienyl)(iodo)iron (152 mg, 0.50 mmol), palladium(II) acetate (5.6 mg, 0.025 mmol), (l.l ,2/ )-iV,iV,iV ,JV -tetramethylcyclohexane-l,2-diamine (6.0 mg, 0.030 mmol), and tetrahydrofuran (1.0 mL) are sequentially added in a 20-mL reaction flask under argon. The mixture is cooled to 0 °C and then phenylmagnesium bromide (1.1-M tetrahy ofiiran solution, 0.68 mL, 0.75 mmol) is added. After the resulting mixture is stirred for 15 min at 0 °C, a saturated ammonium chloride solution (0.2 mL) is added to the reaction mixture. The mixture is filtered through a pad of Florisil, and the filtrate is concentrated. Silica gel column purification (eluent carbon disulfide) of the crude product provided dicarbonyl(cyclopentadienyl)(phenyl)iron 110 mg (87%). ... 

Benzylic C-H bonds can be oxidatively activated and subjected to dehydrogenative coupling with 1,3-dicarbonyl compounds using catalytic amounts of iron(II) chloride and di-ferf-butyl peroxide (DTBP) as an oxidant (Scheme 4-254). ... 

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