Tetracarbonylhydridoferrates

Piperidines have often been prepared by condensation between suitably placed primary amino and carbonyl groups. The simplest cases would be 5-aminopentanals or the corresponding ketones, and the common approach to these is from the nitro compounds by reduction. Syntheses of 3-hydroxypiperidines follow this route (equation 4) (74BSF1001). A number of quinoline syntheses involve the reduction of an o-nitrocinnamyl derivative the simplest uses o-nitrocinnamaldehyde. Potassium tetracarbonylhydridoferrate reduces (5) to quinoline in quantitative yield. If more vigorous reduction is required the aldehyde... 

A. PREPARATION OF ALCOHOLIC OR WATER/THF SOLUTIONS OF POTASSIUM TETRACARBONYLHYDRIDOFERRATE(l-)... 

Potassium tetracarbonylhydridoferrate is a hydride transfer agent that may be used to reduce ketones selectively in high yields (equation 54)205. With diketones a hydroxy ketone is produced. 

Reductionof imidoyl chlorides (1) toimines (2) andamines (J). This reaction can be conducted with sodium tetracarbonylhydridoferrate at 0-25°. Use of excess reagent permits conversion of 2 to 3. The paper presents a possible mechanism. 

Hydrogenation of Knoevenagel products of 2,4-alkanediones over Raney nickel provides a simple route to 3-substituted 2.4-diones. Alternatively, reductive deacetylation can be accomplished using tetracarbonylhydridoferrate(0) in ethanol to prepare alkyl ketones. If the reaction is carried out in THF or acetone, exclusive reduction of the a,p-unsaturated double bond is observed. - Reactions of aldehydes with cyclic 1,3-diketones generally lead to the formation of Michael adducts under standard conditions. Indane-l,3-dione (103) yields Knoevenagel products with different aldehydes, ketones and ketimines, whereas perinaphthindane-l,3-dione (KM) gives the Michael adducts. ... 

Phthalaldehyde has also been employed as a precursor. 2-Arylisoindoles are formed when phthalaldehyde is reacted with primary aromatic amines in the presence of potassium tetracarbonylhydridoferrate. In some examples, reduction to the isoindoline level also occurs, and this is the main pathway when aliphatic amines are employed.62 The reactions of phthalaldehyde with ammonia and with amines in the absence of a reducing agent give complex mixtures. With ammonia, the major products are phthalimidine and 3-(2-cyanophenyl)isoquinoline.6 3... 

Most of the preparations of molecular coordination compounds of iron published in Inorganic Syntheses or elsewhere require the readily available pentacarbonyliron or derivatives thereof. However, pentacarbonyliron is a rather stable compound that needs either thermal or photochemical activation to react. We describe here the selective, high-yield, one-pot synthesis of the title complexes from potassium tetracarbonylhydridoferrate(l — ), easily generated from pentacarbonyliron, a method that can be referred to as a nucleophilic activation of pentacarbonyliron. ... 

Solutions of tetracarbonylhydridoferrate(l — ) salts can be prepared by numerous methods. The most straightforward and widely used involves the reaction of Fe(CO)s and an excess of an alkaline base in protic media. The conventional method to prepare ethanolic solutions of K[FeH(CO)J is to react Fe(CO)5 and 3 equiv of KOH in EtOH at room temperature. The procedure described here uses 2KOH equivalents only and allows the rapid and quantitative preparation of ethanolic K[FeH(CO)4] solutions, which are stable provided that all traces of oxidizing agents are rigorously excluded. 

Isoindoles.—Phthalaldehyde reacts with aromatic amines in the presence of potassium tetracarbonylhydridoferrate, K[HFe(CO)4], to give isoindoles (244) and isoindolines (245) in variable proportions.The pentenyl-isoindole (246) forms the intramolecular Diels-Alder adduct (247) on heating. ... 

Sodium hydrogen carbonate, 457 Sodium hydrogen selenide, 459 Sodium hydrogen telluride, 459-460 Sodium hydrosulfite, 252 Sodium hydroxide, 460-461 Sodium methoxide, 463 Sodium p-methoxythiophenoxide, 421 Sodium 2-mcthyl-2-butoxide, 339 Sodium naphthalenide, 464 Sodium nitronates, 370, 371 Sodium selenophenolate, 212, 307, 397 Sodium sulfide, 360 Sodium tetracarbonylhydridoferrate, 419-420... 

Potassium tetracarbonylhydridoferrate Hydrogenation of carbon-carbon double bonds with -deacylation... 

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