(a) Phthalaldehyde `overset(Conc.NaOH)(to)` Product `(to)` Cannizzaro reaction
(b) `alpha` - Methylacylohexanone `underset(Delta)overset(NaOH)(to)` Product `(to)` Aldol condensation
( c) Toluene `underset(H_(3)O^(+))overset(CrO_(2)Cl_(2)//CS_(2))(to)` Product `(to)` Etard reaction
(d) Benzene `+CO+HCloverset(AlCl_(3))(to)` Product `(to)` Gattermann's Koch reaction
(e) Benezene `+HCN+HCloverset(AlCl_(3))(to)` Product `(to)` Gattermann's aldehyde synthesis
Which of the following is correct set :

Options

A. a,b,c,d
B. a,b,d,e,
C. a,b,c,e
D. a,b,c,d,e

Answer

To solve the question regarding the reactions and their corresponding names, we will analyze each reaction step by step.

### Step 1: Analyze Reaction (a)
**Reaction**: Phthalaldehyde `overset(Conc.NaOH)(to)` Product `(to)` Cannizzaro reaction.

- **Phthalaldehyde Structure**: Phthalaldehyde has two aldehyde groups on a benzene ring.
- **Cannizzaro Reaction**: In the Cannizzaro reaction, one aldehyde undergoes oxidation to form a carboxylic acid, while the other is reduced to an alcohol.
- **Product Formation**:
- One aldehyde group is oxidized to form sodium benzoate (C6H4(COONa)).
- The other aldehyde group is reduced to form benzyl alcohol (C6H5CH2OH).

**Conclusion**: This reaction is correctly identified as a Cannizzaro reaction.

### Step 2: Analyze Reaction (b)
**Reaction**: `alpha` - Methylacylohexanone `underset(Delta)overset(NaOH)(to)` Product `(to)` Aldol condensation.

- **Structure of alpha-Methylacylohexanone**: It has a ketone group and a methyl group at the alpha position.
- **Aldol Condensation**: This reaction involves the formation of a β-hydroxy ketone followed by dehydration to form an α,β-unsaturated ketone.
- **Product Formation**: The aldol product will have a structure where the two carbon chains are linked, and upon heating, water is removed to form the final product.

**Conclusion**: This reaction is correctly identified as an aldol condensation.

### Step 3: Analyze Reaction (c)
**Reaction**: Toluene `underset(H_(3)O^(+))overset(CrO_(2)Cl_(2)//CS_(2))(to)` Product `(to)` Etard reaction.

- **Toluene Structure**: Toluene has a methyl group attached to a benzene ring.
- **Etard Reaction**: In the Etard reaction, toluene is oxidized to benzaldehyde using chromyl chloride.
- **Product Formation**: The product formed is benzaldehyde (C6H5CHO).

**Conclusion**: This reaction is correctly identified as an Etard reaction.

### Step 4: Analyze Reaction (d)
**Reaction**: Benzene `+CO+HCloverset(AlCl_(3))(to)` Product `(to)` Gattermann's Koch reaction.

- **Benzene Structure**: Benzene is a simple aromatic compound.
- **Gattermann's Koch Reaction**: This reaction involves the formylation of benzene to produce benzaldehyde using carbon monoxide and hydrochloric acid in the presence of anhydrous aluminum chloride.
- **Product Formation**: The product formed is benzaldehyde (C6H5CHO).

**Conclusion**: This reaction is correctly identified as Gattermann's Koch reaction.

### Step 5: Analyze Reaction (e)
**Reaction**: Benzene `+HCN+HCloverset(AlCl_(3))(to)` Product `(to)` Gattermann's aldehyde synthesis.

- **Benzene Structure**: Benzene is the same as before.
- **Gattermann's Aldehyde Synthesis**: This reaction involves the introduction of a formyl group to benzene using hydrogen cyanide and hydrochloric acid in the presence of aluminum chloride.
- **Product Formation**: The product formed is again benzaldehyde (C6H5CHO).

**Conclusion**: This reaction is correctly identified as Gattermann's aldehyde synthesis.

### Final Conclusion
All five reactions (a, b, c, d, e) have been correctly identified with their respective names. Therefore, the correct set is:

**Final Answer**: All reactions (A, B, C, D, E) are correctly matched.

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