Potassium Decacarbonylhydridochromate

(M = K)

[61453-56-3]  · C10HCr2KO10  · Potassium Decacarbonylhydridochromate  · (MW 424.21) (M = Na)

[12082-96-1]  · C10HCr2NaO10  · Sodium Decacarbonylhydridochromate  · (MW 408.10)

(selectively hydrogenates a,b-unsaturated carbonyl compounds1)

Physical Data: red crystals.

Solubility: sol THF.

Form Supplied in: not commercially available.

Preparative Methods: prepared by treating Hexacarbonylchromium with Potassium-Graphite or Sodium Amalgam.1

Purification: used in situ following the above preparation.

Handling, Storage, and Precautions: air and moisture sensitive.

Hydrogenation of a,b-Unsaturated Carbonyl Compounds.

Hydrogenation of a,b-unsaturated carbonyl compounds is readily effected by treatment with either potassium or sodium decarbonylhydridochromate. Unsaturated ketones, aldehydes, esters, and nitriles are all reduced by this reagent, with no problems arising from reduction of the carbonyl or nitrile functionalities. The reagent is totally specific for reduction of the a,b-unsaturated site. Neither isolated double bonds, nor the g,d-unsaturated site in a,b,g,d-unsaturated carbonyl compounds are reduced by these reagents. Although these reagents exhibit excellent selectivity, the procedures are operationally more difficult than other reducing agents (eq 1).2

1. Boldrini, G. P.; Umani-Ronchi, A.; Pannunzio, M. Synthesis 1976, 596.
2. Keinan, E.; Greenspoon, N. COS 1991, 8, 523.

James W. Herndon

University of Maryland, College Park, MD, USA

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