oxymetazoline 3

Question 1

list and explain steps 1 of oxymetazoline synthesis?

try to picture the reaction mechanism for each step off the top of your head. (use a pen and paper to right out the correct mechanism and compare you answers with slide 4 )

Answer 1

Step 1: Blanc chloromethylation (‘Blanc reaction’)
HCl (g) with zinc chloride (Lewis acid) & formaldehyde

i.e. adding a methyl chloride group on position 5 on the phenol.

the mechanism is found on slide 4

Question 2

what is the starting compound for oxymetazoline synthesis?

try and draw its structure of the top of your head

Answer 2

2-tert-Butyl-4,6-dimethylphenol

Question 3

2-tert-Butyl-4,6-dimethylphenol is used as _________

Answer 3

Used as an antioxidant to prevent gumming of fuels

Question 4

list and explain steps 2 of oxymetazoline synthesis?

try to picture the reaction mechanism for each step off the top of your head. (use a pen and paper to right out the correct mechanism and compare you answers with slide 5 )

Answer 4

Step 2: Formation of the nitrile (SN2)

by attacking the cl with KCN replacing it with a nitrile

Question 5

list and explain steps 3 of oxymetazoline synthesis?

try to picture the reaction mechanism for each step off the top of your head. (use a pen and paper to right out the correct mechanism and compare you answers with slide 6 )

Answer 5

Step 3: Formation of the imidate

by attacking the nitrile with EtOH / H+ (ethanol and a proton) to get an amine connected to an ether

Question 6

list and explain steps 4 of oxymetazoline synthesis? (final)

try to picture the reaction mechanism for each step off the top of your head. (use a pen and paper to right out the correct mechanism and compare you answers with slide 7)

Answer 6

Step 4: Formation of the imidazole ring

by reacting with NH2CH2CH2NH2 TO REMOVE THE ETHER AND TO FORM THE IMIDAZOLE RING