In which of the following molecules carbon atom marked with asterix (*)is a stereocentre or chiral centre?
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → C* carrying H, Cl, Br and OH
A carbon atom is a stereocentre (chiral centre) when it carries four different groups. In Option (1), C* carries H, Cl, Br and OH, four different groups, so it is chiral.
Why the other options are incorrect
Option (2) — Incorrect. C* carries two H atoms (plus \( \ce{CH3} \) and \( \ce{C2H5} \)); with two identical groups it is not chiral.
Option (3) — Incorrect. C* carries two \( \ce{CH3} \) groups (plus H and OH), as in propan-2-ol; it is not chiral.
Option (4) — Incorrect. C* carries two H atoms (plus F and Cl); it is not chiral.
NCERT (2026-27 edition):
Stereochemical Aspects of Nucleophilic Substitution Reactions – …
