- #1
What is the configuration (R or S) of these molecules?
- Thread starter sd34
- Start date
-
- Tags
- Configuration Molecules
Click For Summary
SUMMARY
The discussion centers on the configuration of two molecules, specifically identifying their stereochemistry as R and S. Participants clarify that the first molecule is R due to the correct prioritization of functional groups, while the second is S, with emphasis on the importance of recognizing all substituents around the stereocenter. A common mistake noted was misassigning priority to COOH over NH2 in the first molecule and overlooking the influence of additional carbon atoms in determining the configuration.
PREREQUISITES- Understanding of stereochemistry and the Cahn-Ingold-Prelog priority rules
- Familiarity with molecular structures and functional groups, specifically COOH and NH2
- Knowledge of how to identify stereocenters in organic molecules
- Ability to visualize and redraw molecular structures for clarity
- Study the Cahn-Ingold-Prelog rules for assigning R and S configurations
- Learn to identify and prioritize functional groups in organic chemistry
- Practice drawing and analyzing stereoisomers using molecular models
- Explore common mistakes in stereochemistry to avoid misassignments
Chemistry students, organic chemists, and anyone involved in molecular configuration analysis will benefit from this discussion.
- #2
mjc123
Science Advisor
Homework Helper
- 1,402
- 801
I think the first is R and the second is S.
Can you explain how you arrived at your answers?
Can you explain how you arrived at your answers?
- #3
sd34
- 9
- 0
mjc123 said:
Yes, it’s correct.
Basically the mistake I made was that I gave the first priority to COOH instead of NH2 in the first molecule, whereas in the second one I forgot to switch from R to S.
- #4
- #5
mjc123
Science Advisor
Homework Helper
- 1,402
- 801
You've forgotten the other C atom on the C 2 atoms from the stereocentre on the chain you labelled 2.
- #6
sd34
- 9
- 0
mjc123 said:
Okay, but isn’t the priority still the same?
- #7
mjc123
Science Advisor
Homework Helper
- 1,402
- 801
No, that C trumps the H on C2 on the other chain.
- #8
sd34
- 9
- 0
mjc123 said:
If it’s not too much of a trouble, could you redraw the molecule?
- #9
mjc123
Science Advisor
Homework Helper
- 1,402
- 801
- #10
sd34
- 9
- 0
mjc123 said:
Thanks a lot! So basically I switched no.1 and no.2 in terms of priority.