13.2 Stereoisomerism

Question 1

What are stereoisomers?

Answer 1

Isomers that have the same structural formula, but a different arrangement of atoms in space

Question 2

What does the E in E/Z Isomerism stand for?

Answer 2

Entgagen (opposite)

Question 3

What does the Z E/Z Isomerism stand for?

Answer 3

Zusammen (together/same)

Question 4

Why does stereoisomersim around double bonds arise?

Answer 4

Rotation around the double bond is restricted, and the groups around each carbon atom are therefore fixed relative to eachother

Question 5

What are the two guidelines that mean a molecule will have E/Z Isomerism?

Answer 5

-Must have a C=C bond
-Must have different groups attached to each atom of the carbon double bond

Question 5

What happens in E isomerism?

Answer 5

The two largest groups are on opposite sides

Question 6

What happens in Z isomerism?

Answer 6

The two largest groups are on the same side

Question 7

What is the rule for cis/trans isomerism?

Answer 7

One of the attached groups on each carbon atom of the double bond must be the same, and must be hydrogen

Question 8

What is the trans isomer the same as? (E or Z)

Answer 8

E

Question 9

What is the cis isomer the same as? (E or Z)

Answer 9

Z

Question 10

What is the Cahn-Ingold-Prelog rule?

Answer 10

The larger the atomic number of the first atom in the group, the higher its priority. If this value is equal, continue to the next atom on the chain.