Question

Select the INCORRECT statement about product(s) of the reaction.

$trans-hex-3-ene \xrightarrow{Br_2 \atop CCl_4} Product(s)$

• A. Products obtained are enantiomers of each other
• B. Reaction follows anti-addition
• C. Product obtained is optically inactive due to internal compensation
• D. In the above reaction rearrangement of carbocation in not possible

Answer 1

Answer: (C)

Product obtained is optically inactive due to internal compensation

Answer 2

The reaction of trans-hex-3-ene with $Br_2/CCl_4$ follows anti-addition, forming a racemic mixture of (3R,4R) and (3S,4S)-3,4-dibromohexane. These are enantiomers. A racemic mixture is optically inactive due to external compensation (cancellation of optical rotation by equal amounts of enantiomers), not internal compensation (characteristic of meso compounds). The reaction proceeds via a cyclic bromonium ion, not a free carbocation, so rearrangements are not possible. Thus, the statement claiming optical inactivity due to internal compensation is incorrect.