Stereochemistry

Question 1

Stereocenter

Answer 1

• A tetrahedral carbon or other atom bonded to four different substituents

Question 2

Chiral Molecules

Answer 2

• Molecules that are not superimposible on their mirror image
• Have enantiomers
• Most simple chiral molecules:
  
  • one stereocenter
  • tetrahedral carbon (or other atom w/ 4 different substituents)

Question 3

Enantiomers

Answer 3

Mirror images of eachother and are stereoisomers of each other

Question 4

Stereoisomers

Answer 4

Isomers that differ in the 3-D arrangement of atoms

Question 5

Enantiomers

Answer 5

• Stereoisomers that are non-superimposable mirror images.
• Different bond connectivities
• Can’t be overlayed in any conformation
• Switch any two groups (but only two groups) to get the enantiomer

Question 6

Meso Compound

Answer 6

Compound that has two or more chirality centers but the whole molecule is achiral

Question 7

Diastereomers

Answer 7

Opposite Configurations at some chirality Centers

Question 8

Anti

Answer 8

Two groups on adjacent carbons oriented at 180^o to each other

Question 9

Syn

Answer 9

Two groups on adjacent carbons oriented at 0º to each other

Question 10

R/S Configurations

Answer 10

1. Look at one stereocenter at a time and assign priority (H always lowest)
2. Arrange so the lowest priority group is pointed away from you
   
   1. Clockwise: R
   2. Counterclockwise: S

Question 11

Meso Compounds

Answer 11

• Have internal symmestry (internal mirror plane)
• Have stereocenters but are achiral