Organic chemistry: Stereochemistry (3)

Organic chemistry: Stereochemistry. Chiral carbons ("stereocenters") vs. chiral molecules. Meso molecules. Enantiomers and diastereomers. R and S naming

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(1) Chiral carbons ("stereocenters") vs. chiral molecules
(2) Continued. Meso molecules. Enantiomers
(3) Continued. Diastereomers. R and S naming
(4) R and S naming continued
(5) Continued


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Category:

Education

Tags:

• organic
• chemistry
• stereochemistry
• chiral
• carbons
• stereocenters
• meso
• enantiomers
• diastereomers
• educational
• college
• student
• education
• MCAT
• exam
• test

[Sonolumino8939]

@junglee786 You need to learn to be grateful for free wonderful information. Ass.

[Laggminator]

Easy to follow

Very good job!

[dorsydoll]

What is R and What is S?

[cerealninjakilla]

@ajinkyakamat2000 I agree. I don't see how the carbon is attached to 4 different substituents. I see a Methyl Bromide ethyl and ethyl.

[soheil1212]

wish every teacher took time like you to explain this confusing branch of chemistry... amazing

[HockeyPlayer58]

@faintsnow You gotta be aware of the fact that horizontal lines are coming out of the board and vertical lines are going into the board. If you rotate the left hand molecule 180 degrees towards you, you are not going to get the right hand side molecule. Moreover the R and S naming for each chiral center will be affected so that type of rotation isn't allowed in fischer projection.

[FaintSnow]

@ 1:56 , if you rotate the molecule towards you 180 degrees, you would have the same molecule. Is it only for clockwise/counter-clockwise rotation or also for 3D rotation?

[Naudins]

Question:

The two molecules he just drawed on 1.55, why aren't they the same? If you rotate it 180 degrees towards you (imagene it coming out of the blackboard) you end up with exactly the same, don't you? Or aren't you allowed to do that in this projection?

[saurabhsacker]

thumbs up to the student for asking good questions.

[reddhawkk]

@ajinkyakamat2000 Group 2 is ch2-ch3 or ethyl. Group 3 is ch3, methyl. Ethyl has a higher priority than methyl. hope that helps

[ajinkyakamat2000]

1 Question; at 6:45... the eg. of R and S naming... isnt it the same group attached at 2 and 3 priority ?