Q.52.

Question

Question: Draw a stepwise mechanism for the following variation of the aldol reaction, often called a nitro aldol reaction.

Step-by-Step Solution

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Answer

Answer

Mechanism

1Step 1: Nitro Aldol Reaction

The Henry- reaction or the nitro-aldol reaction is the C-C bond formation reaction which occurs between a nitroalkane and a carbonyl group-containing compound in the presence of a mild base.

2Step 2: Mechanism of Nitro Aldol Reaction

The base attacks the acidic hydrogen of the nitroalkane to form a carbanionic center which undergoes resonance stabilization with the nitrogen atom.

As a result, a double bond is generated between the nitrogen and the carbon atom which attacks as a nucleophile on the electron-deficient carbonyl carbon of the carbonyl compound. The product contains an additional C-C between the two starting reactants.

3Step 3: Explanation

Stepwise mechanism of the given reaction

Q.51.

Q.53.

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