Chapter 5 Flashcards
R-S convention rule 2 says that
If rule 1 can’t make the decision( all the atoms are the same). Then you work outward from the stereogenic center until a decision is reached. For example an ethyl group has a higher priority than a methyl
R-S convention Rule 1 states that:
Atoms directly attached to the stereophonic center are ranked according to atomic number
Cl>O>C>H
R-S convention rule 3 states
Multiple bonds are treated as if they were an equal number of single bonds
Diastereomers
Stereoisomers that are not mirror images of each other
Meso-compound
Is an achiral diastereomer of a compound with stereogenic centers
R, and S, lactic acid cannot be separated by ordinary achiral methods because
They differ only in chiral properties
What are two achiral methods of seperation?
Distillation or recrystallization
Racemic mixture
Is a 50:50 mixture of a pair of enantiomers
What always gives a racemic mixture of enantiomers?
When a reaction between two achiral reagents leads to a chiral product.
Resolution
Is the process of separating a racemic mixture into its enantiomers
Conformers
Interconvertible by rotation about single bonds
Configurational isomers
Not Interconvertible by rotation, only by breaking and making bonds
Chiral
Mirror image not superimposable on itself
Achiral
Molecule and mirror image are identical
Enantiomers
Mirror images; have opposite configurations at all stereogenic centers
