Q9P - Organic Chemistry (Mcmurry)

Question

Treatment of a 1,3-diketone such as 2,4-pentanedione with base does not give an aldol condensation product. Explain.

Step-by-Step Solution

Answer

Due to the formation of the stable compound at equilibrium, treatment of a 1,3-diketone such as 2,4-pentanedione with base does not give an aldol condensation product.

Formation of enolate ions:

 

Results of treatment

Due to the formation of stable enolate ion as seen in [A] enolate ion at equilibrium, it becomes unreactive 

Hence,1,3-diketone on treatment with base does not give an aldol condensation while in the case of [B] enolate ion it is unstable and forms a negligible amount of product.