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Organic chemistry-Cheat sheet for stereochemistry

If you are a student studying organic chemistry, then you must know stereo-chemistry. For many people it's very difficult to understand. Usually what they expect you to do is to recognize two given molecules, whether they are the same molecule, enantiomers or diastereomers. There is a short cut..

Assuming that you already know how to name a stereogenic center (R,S method ) lets begin it. Remember there must be two stereogenic centers to be diastereomers. 

So first name two molecules using R and S. IF a one naming is the exact opposite of the other one, then that pair is enantiomers. For an example, RR and SS, RSR and SRS, RS and SR etc.( Even though there are hundred stereogenic centers the name should be opposite.) 

IF names are the same then that is the same molecule. Eg : RR and RR, SS and SS. RRSS and RRSS etc.

IF names are not opposite or not same then they are diastereomers. Eg: RRS and RRR, SSR and SSS SRS and SSS etc.

It's really simple, isn't it? :)

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  1. UnknownApril 30, 2017 at 8:02 PM

    Thank you very much,, reallly really helpfull...

    ReplyDelete
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