Potassium tetracarbonylhydridoferrate

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. 

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. ... 

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. ... 

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

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