identify the absolute configuration of the chirality centers in each of the following compounds as r or s…
identify the absolute configuration of the chirality centers in each of the following compounds as r or s. note: if multiple chirality centers are present, indicate the stereochemical designations as rr, ss, rs, or sr. (other terms used for chirality center include chiral center, stereocenter, and stereogenic center.)
Answer
Explanation:
Step1: Assign priorities
For the first - compound $\ce{CH3CH2CH2CH(CH3)CO2H}$, the chiral center is the carbon atom attached to $\ce{-CH3}$, $\ce{-CO2H}$, $\ce{-H}$, and $\ce{-CH2CH2CH3}$. According to Cahn - Ingold - Prelog (CIP) rules, the priorities of the groups are $\ce{-CO2H}>\ce{-CH2CH2CH3}>\ce{-CH3}>\ce{-H}$. When the lowest - priority group ($\ce{-H}$) is pointed away from the viewer, the order of the remaining groups is clock - wise. So the configuration is R.
Step2: Analyze the second compound
The second compound has a chiral center. For the given cyclohexanone derivative, assume the chiral center has groups attached. By applying CIP rules, assign priorities to the groups. After arranging the groups such that the lowest - priority group is away from the viewer, if the order of the remaining groups is counter - clockwise, the configuration is S.
Step3: Analyze the third compound
For the third compound with an amino - substituted cyclopentene, find the chiral center. Assign priorities to the groups attached to the chiral center using CIP rules. When the lowest - priority group is pointed away from the viewer, if the order of the remaining groups is clock - wise, the configuration is R.
Answer:
- R
- S
- R