Aniline can be obtained by :
(a) `C_(6)H_(5)COOHunderset(H^(o+))overset(N_(3)H)(to)`
(b)`C_(6)H_(5)CONH_(2)underset(Delta)overset(Br_(2)//KOH)(to)`
( c) `C_(6)H_(5)COOHunderset(Delta)overset(NH_(3))(to)`
(d) `C_(6)H_(5)NO_(2)overset(Fe+H_(2)O)(to)`

Options

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

Answer

To determine which reactions yield aniline from the given options, we will analyze each reaction step by step.

### Step 1: Analyze Option A
**Reaction:**
\[ C_6H_5COOH + H_3N \xrightarrow{H^+} \text{(to)} \]

- **Starting Material:** Benzoic acid (\(C_6H_5COOH\))
- **Reagents:** Hydrozoic acid (\(H_3N\)) in acidic conditions.
- **Expected Product:** Aniline (\(C_6H_5NH_2\))

**Explanation:**
In this reaction, benzoic acid reacts with hydrozoic acid in acidic conditions, leading to the formation of aniline through a process known as Schmidt's reaction.

**Conclusion:** Option A produces aniline.

### Step 2: Analyze Option B
**Reaction:**
\[ C_6H_5CONH_2 \xrightarrow{\Delta} \text{Br}_2/KOH \text{ (to)} \]

- **Starting Material:** Benzamide (\(C_6H_5CONH_2\))
- **Reagents:** Bromine in the presence of KOH, followed by heating.
- **Expected Product:** Aniline (\(C_6H_5NH_2\))

**Explanation:**
This reaction is known as the Hofmann degradation reaction. Benzamide reacts with bromine and KOH, resulting in the loss of one carbon atom and the formation of aniline.

**Conclusion:** Option B produces aniline.

### Step 3: Analyze Option C
**Reaction:**
\[ C_6H_5COOH + NH_3 \xrightarrow{\Delta} \text{(to)} \]

- **Starting Material:** Benzoic acid (\(C_6H_5COOH\))
- **Reagents:** Ammonia (\(NH_3\)), heated.
- **Expected Product:** Aniline (\(C_6H_5NH_2\))

**Explanation:**
In this case, benzoic acid reacts with ammonia under heat. However, this reaction leads to the formation of benzamide (\(C_6H_5CONH_2\)) rather than aniline. Therefore, there is no formation of aniline in this step.

**Conclusion:** Option C does not produce aniline.

### Step 4: Analyze Option D
**Reaction:**
\[ C_6H_5NO_2 \xrightarrow{Fe + H_2O} \text{(to)} \]

- **Starting Material:** Nitrobenzene (\(C_6H_5NO_2\))
- **Reagents:** Iron in the presence of water.
- **Expected Product:** Aniline (\(C_6H_5NH_2\))

**Explanation:**
In this reaction, nitrobenzene is reduced by iron in the presence of water, converting the nitro group (\(-NO_2\)) into an amino group (\(-NH_2\)), thus forming aniline.

**Conclusion:** Option D produces aniline.

### Final Conclusion
Based on the analysis:
- **Option A:** Produces aniline.
- **Option B:** Produces aniline.
- **Option C:** Does not produce aniline.
- **Option D:** Produces aniline.

Thus, the correct options that yield aniline are A, B, and D.

### Final Answer:
The correct options are A, B, and D.

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