R and S Configuration Practice Problems

R and S configurations are essential in understanding almost all the concepts in Stereochemistry. In this video we will practice assigning the Absolute Configuration - R and S using the Cahn-Ingold-Prelog priority rules for ranking substituents. These practice problems will cover determining the R and S configuration for simple molecules and for the ones where you need to look further into the layers of atom’ connectivity to determine the priority, and for the ones where the lowest priority is pointing towards you. Molecules can have more than one chirality center and, in these cases,, you need to determine the absolute configuration for each chiral center. These types of problems are also covered in this exercise.

The complete video solution to all the 12 IR practice problems can be found at:

For more topics and practice problems of Organic Chemistry visit:


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[elias]

Not the full solution and not in alphabetical order...

[valeguidi]

G is definitely R; why would you prioritize a nitrile over bromine if bromine has a larger atomic number... So it originally looks like S, and since the hydrogen is facing towards us, you must flip the configuration to R.

[cousinfam]

for d) how did you know the wedge ch3 get priority than the ch3 without wedge

[technify]

For those confused about G the reason why it is not S is due to Hydrogen the lowest priority facing forward, if the lowest priority faces towards the front you take whatever configuration it is and flip it. Since the configuration for G is S I see where the confusion comes from but due to H facing the front (indicated by the solid line not dashed) you flip it making it R configuration. Hope this helps =)

[parveenmadaan]

Sir please provide the answer key of left ques

[_slvya]

Bro where is part 2, can someone hsare the answers i want to verify mine

[ajaypatha]

How do you tell if H is pointing towards us or away from us?

[nishabhardwaj]

I think g has s configuration and I specially wanted to know the configuration of (e)

[santamaria]

Thank you so much, you are a lifesaver, I struggled for days to understand this. Just 2 minutes video I understood. God bless you.

[bojopolis]

Don't waste your time, solves less than half and the website with the solutions they want you to register for