mnick12 - 10-9-2011 at 11:13
Hello everyone,
I am having a little bit of trouble with 4-ethoxyphenol. There are a number of threads dedicated to the synthesis of 4-methoxyphenol, but not many to
the ethyl ether. Long story short 4-ethoxyphenol was made from HQ, BQ, ethanol, and H2SO4 according to a well known method. Anyways after
neutralization, brine extraction, and vacuum distillation I was left with a pale viscous yellow oil with a characteristic smell. Now the problem is
this oil refuses to crystallize. Even after cooling and agitation.
Any ideas?
Thanks
Nicodem - 10-9-2011 at 13:23
Let me guess: You used toluene for the extraction and short path distillation?
p-Ethoxyphenol has a relatively low mp of 64-67 °C. Any impurity or residual solvent, toluene in particular, is likely to make the crystallization
difficult (same case as with p-methoxyphenol). You could mix with some petroleum ether (or equivalent) and then letting the biphasic mixture stay in
the refrigerator. If the fault is on a residual solvent, then this treatment should induce crystallization (or at least solidification). If it is due
to mp depression caused by impurities, it might not help. In such case doing this same treatment using an water/ethanol mixture (try from 3:1 to 1:1)
might perform better (depending on the nature of the main impurities).
Is the product is TLC homogeneous?
mnick12 - 11-9-2011 at 20:50
No I partially neutralized the H2SO4, distilled of 55ml of ethanol, poured the solution into brine then extracted with DCM (wasnt even necessary the
ethoxyphenol goop is insoluable in brine). I then set up a short path vacuum distillaion, the oil came over at about 170 C. I have not taken TLC yet
but I will next time im in my lab. I will also try the water ethanol treatment thanks for the ideas.