Chapter 6: 6.6 Dihydroxylation

Question 1

List:

Characteristics of Dihydroxylation Reactions

Answer 1

1. Occur in multiple steps
2. Adds two alcohols across an alkene bond to form a diol
3. There is no Markovnikov or anti-Markovnikov addition since the two groups added are the same
4. The two alcohols are added syn (on the same side) for stereochemical outcome

Question 2

Define:

Diol

Answer 2

di- for “two”; -ol for “alcohol”

Question 3

State:

Steps of Dihydroxylation reaction

Answer 3

1. A concerted reaction (occurs in a single step) where a 5-membered metallocycle is formed using the OsO4 or KMnO4
2. Hydrolysis with a dilute base gives the diol

Question 4

True or False:

You don’t need to know the mechanism of dihydroxylation reaction

Answer 4

True

Question 5

True or False:

Dihydroxylation reactions are stereospecific

Answer 5

True