JEE Main · 2025 · 22 Jan 2025 · Shift 1 · General Organic Chemistry

How many different stereoisomers are possible for the given molecule?

(A)3
(B)1
(C)2
(D)4✓ Correct

Answer: (D)

Solution

The molecule is

C H_{3} - C * H (O H) - C H = C H - C H_{3}

(pent-3-en-2-ol), which carries two independent stereogenic features:

C2 is a chiral centre, bonded to four different groups (

- H, - O H, - C H_{3}, - C H = C H C H_{3}

), giving R and S configurations.

The C3=C4 double bond carries an

H

and a different group on each carbon, so cis and trans arrangements both exist.

Since the two features are independent of each other, the total count of stereoisomers is

2 \times 2 = 4

: (R,cis), (R,trans), (S,cis) and (S,trans).

JEE Main · 2025 · 22 Jan 2025 · Shift 1 · Single correct option

Practise more: all JEE Main PYQs on General Organic Chemistry →

More JEE Main questions on General Organic Chemistry

From the following, the least stable structure is:
JEE Main 2026View solution →
Identify correct statement from the following:

A. Propanal and propanone are functional isomers.
B. Ethoxyethane and methoxypropane are metamers.
C. But-2-ene shows optical isomerism.
D. But-1-ene and but-2-ene are functional isomers.
E. Pentane and 2, 2-dimethyl propane are cha …
JEE Main 2026View solution →
Match List-I with List-II.

List-I (Pair of Compounds):
A. 2-Methylpropene and but-1-ene
B. Cis-but-2-ene and trans-but-2-ene
C. 2-Butanol and diethyl ether
D. But-1-ene and but-2-ene

List-II (Type of Isomers):
I. Stereoisomers
II. Position isomers
III. Chain isomers
IV. Functio …
JEE Main 2026View solution →
Given below are two statements:

Statement-I: Compound (X), shown below, dissolves in $NaHCO_{3}$ solution and has two chiral carbon atoms

Statement-II: Compound (Y), shown below, has two carbons with $sp^{3}$ hybridization, one carbon with $sp^{2}$ an …
JEE Main 2026View solution →
The IUPAC name of the following comopound is :
JEE Main 2026View solution →
Consider all the structural isomers with molecular formula $C X_{5} H X_{11} Br$ are separately treated with KOH (aq) to give respective substitution products, without any rearrangement. The number of products which can exhibit optical isomerism from these is ____ .
JEE Main 2026View solution →