Disodium tetracarbonylferrate

Collmans reagent

White solid

Fixed

Template: Infobox chemical / molecular formula search available

Natriumtetracarbonylferrat is an inorganic compound with the formula Na2FeC4O4. There is an air-sensitive, colorless solid whose Tetrahydrofuranaddukt is used in organic chemistry under the name Collmans reagent for the synthesis of aldehydes from alkyl bromides. Collman described the compound as a transition metal equivalent to Grignard compounds.

Representation

Natriumtetracarbonylferrat is accessible by reduction of iron pentacarbonyl with dissolved in liquid ammonia sodium.

Alternatively can be used sodium amalgam as a reducing agent in tetrahydrofuran. In this method, the resulting complex can be converted directly into the further reaction steps in a one-pot reaction.

Use

The connection can be used for the conversion of primary alkyl bromides into the corresponding aldehydes. In the first step occurs with the formation of the sodium alkyl complex.

The addition of triphenylphosphine and subsequent acidification with acetic acid, the aldehyde is released.

Primary alkyl complex formed can be converted into the carboxylic acid by triphenylphosphine in the acyl complex, and by oxidation with oxygen, followed by acidification. By oxidation with halogens of the acyl complex is converted to the carboxylic acid chlorides.

If, instead of acid chlorides to alkyl bromides with Natriumtetracarbonylferrat, put the resulting acyl complexes by reaction with mineral acids to aldehyde free.