How do you prioritize the groups on chiral centers?

1 Answer
Aug 11, 2015

The Cahn-Ingold-Prelog sequence rules assign priorities to the groups attached to each chiral centre.


  1. The atom with higher atomic number receives higher priority.
  2. If there is a tie, we go one bond further out until we come to the earliest difference.
  3. If there is still a tie, we keep going further out until we find a difference.
  4. Double and triple bonds are treated as if they were separate single bonds to the same atom.

Here's an example of how to assign relative priorities.