Reduction of Aldehydes and ketones

Addition of organometallic reagents to Aldelydes and ketones

Organometallic reagents (RLI or RMgX) react with aldehydes and ketones to give alcohols.

Use of RLi

 

 

 

    
 

Reaction with RMgX

In this reaction the intermediate alkylmagnesium halide is hydrolysed using dilute acid or aqueous ammonium chloride in the case of tertiary alcohols

 

    

 

 

 

Use of Lithium tetrahydridoaluminate (III), ( LiAlH₄)

 

Primary and secondary alcohols can be prepared from the reduction of aldehydes and ketones using Lithium tetrahydridoaluminate (III), LiAlH₄ in dry ether.

 

For example:

 

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p style=”margin-left: 11pt”>Lithium tetrahydridoborate (III), LiBH₄, in dry ether, a milder reducing agent can also be used as an alternative reagent.