Enantiomers rotate plane polarized light the same magnitude




















- Slides: 20




Enantiomers rotate plane polarized light the same magnitude, but opposite directions. clockwise rotation – dextrarotatory (d or +) counterclockwise rotation – levorotatory (l or -) racemic mixture – racemate 50: 50 mixture of enantiomers (d, l or ±) No relationship between d, l and R, S.


Designating the Configuration of Enantiomers Step 1: Assign priorities 1 (highest) to 4 (lowest) to the four groups attached to the chirality center using the Cahn-Ingold-Prelog sequence rules. Step 2: View the molecule so the bond from the chirality center to group 4 is pointed away from you. 1 to 2 to 3 to 1 clockwise R (rectus) 1 to 2 to 3 to 1 counterclockwise S (sinister)

1 to 2 to 3 to 1 is counterclockwise, so S 1 to 2 to 3 to 1 is clockwise, so R

1 to 2 to 3 to 1 is counterclockwise, so S 1 to 2 to 3 to 1 is clockwise, so R

absolute configuration: the actual 3 -D arrangement of groups around a chirality center relative configuration: the configuration of one compound relative to another

absolute configuration: the actual 3 -D arrangement of groups around a chirality center relative configuration: the configuration of one compound relative to another

Properties of Enantiomers Enantiomeric molecules are only different in a chiral environment. They have identical mp, bp, heat of combustion, solubility in H 2 O They have different solubility in one enantiomer of a chiral solvent rate of reaction with one enantiomer of a chiral reagent

Resolution: Separating Enantiomers make environment chiral so enantiomers have different properties 1. react with one enantiomer of a chiral compound separate diastereomers and regenerate 2. react with a chiral reagent (enzyme) 3. chromatography with a chiral stationary phase

enantiomers to be separated one enantiomer of a chiral amine diastereomeric salts one diastereomer one pure enantiomer

Reactions that Produce Enantiomers R 50% Reactants (achiral or racemic) (optically inactive) S 50% Products (racemic) (optically inactive)

Other Chiral Compounds tetrahedral atoms other than C

pyramidal atoms These compounds have been resolved.

substituted allenes

biphenyls has been resolved half-life for racemization is 78 min at 118 o. C

helical molecules

Ampere maxwell law
Polarized light definition
Data plane control plane and management plane
Parsec distance
Light light light chapter 23
Into the light chapter 22
Light light light chapter 22
Polarized wave
Non polarized electrode
Polarized physics
Polarized pluralist model
Reflection absorption
Homunculus
Stereoisomers always possess handedness.
Properties of isomers
Enantiomers vs epimers
Constitutional isomers
Are cis and trans diastereomers
Superimposable mirror image
Cyclisation of fructose
Resolution of enantiomers