Question

The total number of possible stereoisomers for 3-bromo-2-butanol are

• A. 2
• B. 4
• C. 6
• D. 8

Answer 1

The Correct Option is B

To determine the total number of stereoisomers for 3-bromo-2-butanol, we need to consider the chiral centers in the molecule. A stereoisomer is one of several forms of a compound with the same connectivities but a different arrangement of atoms in space.

Step-by-Step Explanation: 

1. Identify Chiral Centers: A chiral center or a stereogenic center is a carbon atom that is bonded to four different groups. In 3-bromo-2-butanol (CH₃-CHOH-CHBr-CH₃), there are two chiral centers:
   • Carbon 2 (C-2), which is bonded to -OH, -CH₃, -H, and -CHBr-CH₃.
   • Carbon 3 (C-3), which is bonded to -CH(OH)-CH₃, -H, -Br, and -CH₃.
2. Calculate the Number of Stereoisomers: The number of possible stereoisomers for a molecule is given by the formula \(2^n\), where \(n\) is the number of chiral centers. In this case, \(n = 2\), so the number of stereoisomers is \(2^2 = 4\).
3. The stereoisomers include both enantiomers and diastereomers. Since there are 2 chiral centers, this leads to four stereoisomers: two pairs of enantiomers.

Therefore, the total number of possible stereoisomers for 3-bromo-2-butanol is 4. This corresponds to the correct option, 4.