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NEET CHEMISTRYHaloalkanes and HaloarenesMedium

Question

The reaction of C6H5CH=CHCH3\text{C}_6\text{H}_5\text{CH=CHCH}_3 with HBr\text{HBr} produces:

A

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B

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C

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D

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Step-by-Step Solution

The reaction proceeds via an electrophilic addition mechanism. The proton (H+\text{H}^+) from HBr\text{HBr} attacks the alkene double bond to form the most stable carbocation intermediate. Between the two possible carbocations, C6H5C+HCH2CH3\text{C}_6\text{H}_5\text{C}^+\text{HCH}_2\text{CH}_3 (a benzylic secondary carbocation) is significantly more stable than C6H5CH2C+HCH3\text{C}_6\text{H}_5\text{CH}_2\text{C}^+\text{HCH}_3 (a standard secondary carbocation) because of strong resonance stabilization from the adjacent phenyl ring. The bromide ion (Br\text{Br}^-) then attacks this stable benzylic carbocation to form 1-bromo-1-phenylpropane (C6H5CH(Br)CH2CH3\text{C}_6\text{H}_5\text{CH(Br)CH}_2\text{CH}_3) as the major product. Since the exact structural options are missing from the input text, the precise correct option cannot be visually verified.

Exam Context & Concepts Covered

This question aligns with the NEET CHEMISTRY syllabus, specifically targeting concepts from Haloalkanes and Haloarenes. Mastering this topic is crucial for scoring well in the upcoming medical entrance examinations. Solving conceptually related problems will help you understand the nuances of these concepts and improve your problem-solving speed.

CHEMISTRYHaloalkanes and Haloarenesreactiontextctexthtextchchchtexthbrproduces

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