Which of the following compounds has an asymmetric center?

• A. ${\mathrm{CH}}_3\mathrm{CHBrClF}$
• B. ${\mathrm{CH}}_3{\mathrm{CH}}_2\mathrm{OH}$
• C. ${\mathrm{CH}}_3{\mathrm{CH}}_2\mathrm{CH}{3}_{}$
• D. ${\mathrm{CH}}_2\mathrm{Cl}$

Answer: (A)

Verified step by step guidance

1. Identify what an asymmetric center (chiral center) is: a carbon atom bonded to four different groups.
2. Examine each compound and look for carbon atoms that have four distinct substituents attached.
3. For the compound \( \mathrm{CH_3CHBrClF} \), focus on the second carbon (the one bonded to Br, Cl, F, and the methyl group). Since it is attached to four different atoms/groups, this carbon is an asymmetric center.
4. For the compound \( \mathrm{CH_3CH_2OH} \), check each carbon: the first carbon is bonded to three hydrogens and one carbon (not four different groups), and the second carbon is bonded to two hydrogens, one carbon, and one OH group (also not four different groups). So, no asymmetric center here.
5. For the compounds \( \mathrm{CH_3CH_2CH_3} \) and \( \mathrm{CH_2Cl} \), similarly verify the substituents on each carbon. None have four different groups attached, so no asymmetric centers.