- #1
What is the configuration (R or S) of these molecules?
- Thread starter sd34
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- Configuration Molecules
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Discussion Overview
The discussion revolves around determining the configuration (R or S) of specific molecules, focusing on the assignment of priorities to substituents around stereocenters. It includes technical reasoning and clarification of concepts related to stereochemistry.
Discussion Character
- Technical explanation
- Conceptual clarification
- Debate/contested
Main Points Raised
- Some participants assert that the first molecule is R and the second is S, seeking explanations for these assignments.
- One participant acknowledges a mistake in assigning priority to substituents in the first molecule, suggesting that COOH was incorrectly prioritized over NH2.
- Another participant questions why a specific carbon is designated as S rather than R, prompting a discussion on priority assignments.
- Several participants point out the oversight of considering another carbon atom in the priority ranking, which may affect the configuration determination.
- There is a contention regarding whether the priority remains the same despite the presence of additional carbon atoms in the chain.
- One participant emphasizes that a particular carbon takes precedence over hydrogen in the priority ranking.
- A participant requests a redrawing of the molecule to clarify the priority assignments.
Areas of Agreement / Disagreement
Participants express differing views on the correct priority assignments and configurations, indicating that multiple competing perspectives remain unresolved.
Contextual Notes
Limitations include potential missing assumptions regarding the stereochemistry rules and the specific configurations of the molecules discussed, which are not fully resolved in the conversation.
- #2
mjc123
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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
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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
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You've forgotten the other C atom on the C 2 atoms from the stereocentre on the chain you labelled 2.
- #6
sd34
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mjc123 said:
Okay, but isn’t the priority still the same?
- #7
mjc123
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No, that C trumps the H on C2 on the other chain.
- #8
sd34
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mjc123 said:
If it’s not too much of a trouble, could you redraw the molecule?
- #9
mjc123
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- #10
sd34
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mjc123 said:
Thanks a lot! So basically I switched no.1 and no.2 in terms of priority.