Consider the following sequence of reactions :
`C_6H_5CH_3overset(Cl_2)rarrp-ClC_6H_4CH_3overset(NBS)rarr(X) overset(Mg)rarr(Y)overset((i)"ethylene oxide")rarr(Z) `
Final product (Z) is

Options

A. `p - ClC_6H_4CH_2CH_2OH`
B. `p- ClC_6H_4CH_2CH_2CH_2OH`
C. `p-(HOCH_2CH_2) - C_6H_4CH_2Br`
D. `p - (HOCH_2CH_2)-C_6H_4CH_3`

Answer

To solve the given sequence of reactions step by step, we will analyze each reaction and determine the final product (Z).

### Step 1: Chlorination of Toluene
The starting compound is toluene (C₆H₅CH₃). When toluene reacts with chlorine (Cl₂), an electrophilic aromatic substitution occurs. The methyl group (CH₃) is an electron-donating group and directs the incoming electrophile (Cl) to the ortho and para positions of the benzene ring.

**Major Product**: The para-substituted product will be formed predominantly due to symmetry. Thus, we get p-chlorotoluene (p-ClC₆H₄CH₃).

### Step 2: Bromination with N-Bromosuccinimide (NBS)
Next, we react p-chlorotoluene with N-bromosuccinimide (NBS). NBS generates bromine radicals (Br·) under light or heat conditions. The bromine radical will abstract a hydrogen atom from the benzylic position (the carbon next to the benzene ring), resulting in the formation of a benzylic radical.

**Product**: The product after this reaction is p-chloro-α-bromotoluene (p-ClC₆H₄CBrCH₃).

### Step 3: Formation of Grignard Reagent
The next step involves reacting the p-chloro-α-bromotoluene with magnesium (Mg) in dry ether. This reaction converts the halogen into a Grignard reagent.

**Product**: The product formed is p-chloro-α-bromotolyl magnesium bromide (p-ClC₆H₄CBrCH₃MgBr).

### Step 4: Reaction with Ethylene Oxide
The Grignard reagent then reacts with ethylene oxide. The nucleophilic carbon of the Grignard reagent attacks the less hindered carbon of the ethylene oxide, leading to ring opening.

**Product**: This reaction will result in the formation of an alcohol after hydrolysis. The product will be p-chloro-α-bromotolyl-ethanol (p-ClC₆H₄C(OH)(CH₂CH₃)).

### Final Product (Z)
After hydrolysis, the final product (Z) is:
- p-Chloro-α-bromotolyl-ethanol (p-ClC₆H₄C(OH)(CH₂CH₃))

### Summary of Final Product (Z):
The final product (Z) is p-Chloro-α-bromotolyl-ethanol.

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