Ferrate sodium tetracarbonyl

Sodium Tetracarbonyl Ferrate. An extremely useful organoiron reagent is sodium tetra-carbonyl ferrate [Na2Fe(CO)4], usually prepared by reduction of iron pentacarbonyl. The synthetic utility of this reagent lies in its ability to react with alkyl halides in a stepwise manner, including the reaction with two different alkyl halides, as reported independently by Cooke and by Collman and co-workers. - When sodium tetracarbonyl ferrate reacted with 1-bromooctane, a trigonal bipyramidal complex (715) was formed 

Chapter 8. Nucleophilic Species That Form Carbon-Carbon Bonds 

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Synthesis ttf aliphatic carhoxySe acids, esters, and anodes. Sodium tetracarbonyl-ferrate(-ll) (1) reacts with aliphatic halides and tosylates to give anionic alkyltetra-carbonyliron(O) complexes (2). In the presence of carbon monoxide these undergo... 

KETONES Lithium diisopropylamide. Nickel carbonyl. Sodium tetracarbonyl-ferrate(-II). Thallium(III) nitrate. 2,4,4,6-Tetramethyl-5,6-dihydro-l,3-(4 I)-oxazine. Triphenylmethyl hexafluorophosphate. y-KETONITRILES Sodium cyanide. (3-LACTONES Silver nitrate. y-LACTONES a-Chloro-N-cyclohexylpro-panaldoxime. 

Tricarbonyliron complexes of cyclobutadienes. Roberts et al. have reported a useful synthesis of (2) by reaction of (1) with sodium tetracarbonyl-ferrate in THF. Use of diiron nonacarbonyl leads to (2) in lower yields. The... 

The tetrachlorodiester (431), prepared from the photoaddition product of dichloro-ethylene and dichloromaleic anhydride, reacts directly with sodium tetracarbonyl-ferrate to give the functionalized cyclobutadiene complex (432) in 30—40% yield. The vicinal diester groups have been modified to give a wide variety of 1,2-disubsti-tuted cyclo butadiene complexes. 

Acyl carbonyl ferrates are involved as intermediates in two preparations of aldehydes. Alkyl bromides react with sodium tetracarbonyl ferrate(—ii) (from iron pentacarbonyl and sodium) by a process of oxidative addition to furnish the ferrate(—i) (124) this species rearranges on treatment with triphenylphosphine to a phosphonium-substituted acyl ferrate(—i) (125), which is subsequently cleaved by acetic acid to the homologous aldehyde, as outlined in Scheme 46. A related procedure employs reaction of an acid halide with sodium tetracarbonyl ferrate(—ii) to afford the acyl ferrate(—i) (126) directly this species is also cleaved by acetic acid, and affords yet another method for the reduction of acid halides to aldehydes. 

A 4% sodium amalgam is prepared from the careful addition of sodium (3 g, 130 mmol), in small portions, to mercury (650 g, 3.25 mol), which is rapidly stirred. The amalgam is allowed to return to room temperature over 1 h, and then a tetrahydro-furan (100 mL) solution of tetracarbonyl(dicyclopentadienyl)diiron (10.62 g, 30 mmol) is added in one portion and is efficiently stirred for 2 h. The amber tetrahydrofuran solution of sodium dicarbonyl(cyclopentadienyl)ferrate is separated from the amalgam and transferred to a new flask via syringe. This solution is cooled to 0 °C and l-bromo-2,2-di-methoxypropane (llg, 60 mmol) in tetrahydrofuran (10 mL) is added dropwise over 30 min. The yellow-brown solution is stirred at 0 °C for a further 30 min and then at room temperature for 3 h. The solvent is removed, and the residue is extracted with pentane (ca. 

A solution of sodium dicarbonyl(cyclopentadienyl)ferrate prepared from the dicarbonyl(T] -cyclopentadienyl)iron dimer [Cp(CO)2pe]2 (4.11 g, 11.6 mmol) and sodium amalgam (2%, 35.3 g) in tetrahydrofuran (80 mL) is added slowly at -78 °C to a solution of 4-bromo-2//-chromene-3-carbaldehyde (5.5 g, 23 mmol) in tetrahydrohiran (70 mL). The mixture is stirred at -78 °C for 1 h and then allowed to warm to room temperature over a period of 1 h. The solvent is evaporated in vacuo, and the residue is dissolved in diethyl ether/acetone (1 1) and subsequently purified by column chromatography on silica gel. With petroleum ether/diethyl ether (2 1) tetracarbonyl(dicyclopentadienyl)diiron is separated, whereas with diethyl ether/acetone (1 1) the alkenyl-Fp complex is obtained. The solvent is evaporated and the yellow-brown solid is dissolved in dichloromethane (200 mL), dried (magnesium sulfate), and the solution concentrated in vacuo to yield the q -alkenyl-Fp complex as a yellow-brown, amorphous solid 6.9 g (89%). ... 

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