Arbacluce
Harmless
Posts: 8
Registered: 18-10-2015
Member Is Offline
Mood: No Mood
|
|
Salsalate question
Hi
I wanted to make phenol by decarboxylation of salicylic acid http://www.sciencemadness.org/talk/viewthread.php?tid=27617
Acid melted and it started bubbling but in destilatin flask there was no crystals of phenol, only colorless liquid but temperature was 25C i thought
that is supercooled phenol but after shaking, it didn't want to crystallize. Smell of this dense oil is nice, and reaction mixture that i poured into
cold water also didn't crystallize but form orange/brown oil that sink to the bottom. Is this Salsalate?
[Edited on 18-10-2015 by Arbacluce]
|
|
|
UC235
National Hazard
Posts: 565
Registered: 28-12-2014
Member Is Offline
Mood: No Mood
|
|
Did you redistill the product to remove water and salicylic acid that was carried over? A small amount of water is sufficient to depress phenol's
melting point such that it remains liquid at room temperature since it only melts at 41C when very pure.
Salsalate is a crystalline solid melting at 137C. I guarantee you didn't distill any though it may form as an intermediate in the decarboxylation.
Orange/Brown would indicate phenol oxidation products.
|
|
|
Arbacluce
Harmless
Posts: 8
Registered: 18-10-2015
Member Is Offline
Mood: No Mood
|
|
No. I didn't redistill it., you are right  .
|
|
|
UC235
National Hazard
Posts: 565
Registered: 28-12-2014
Member Is Offline
Mood: No Mood
|
|
If you didn't throw it out, you can steam distill to recover the phenol (phenol dissolves to about 8% in water so a lot of it will not be in the lower
organic phase). Saturate the distillate with salt and extract several times with dichloromethane, ether, or ethyl acetate. Dry with Magnesium sulfate
(CaCl2 will react, probably), and strip the solvent.
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
