Identifying Chiral Centers

Identifying the chiral carbons or chiral centers.

1. Identify all sp3-hybridized carbon atoms.

   • sp2 and sp hybridized carbons can NOT be chiral
   • be wary of implied hydrogens

2. Determine which sp3-hybridized carbons have 4 different groups attached.

   • CH₂ and CH₃ are NOT chiral centers

3. Check for non-carbon chirality centers

   • Conformationally rigid N or S compunds

4. Count the total number of chirality centers

Can you find all 8 chiral centers in cholesterol shown below.

Cholesterol

1. Identify all sp3-hybridized carbon atoms.

   

2. Determine which sp3-hybridized carbons have 4 different groups attached.

   

3. Check for non-carbon chirality centers

   • There are none.

4. Count the total number of chirality centers

   • 8 total stereocenters