SWIM did the wacker O2 method. The ketone came over at
about 130-140 deg. C @30 PSI vacuum. It smelled like the
stuff and was a yellow with a very slight hint of greenish
to it. It definately didnt smell like safrole. Does
isosafrole smell very similar to safrole?
SWIM tried a bit of it with the bisulfite addition
method,it wasnt an instant reaction, but SWIM got some
crystals. SWIM found the bisulfite method isnt always
accurate, sometimes SWIM gets precipitate, sometimes not
(even though the ketone always smells like it should).
Anyway.... The yield from this step was decent for
starters, around 50% ketone.
SWIM Proceeded to do a sodium cyanoborohydride reduction:
175g MD-P2P, 1.5L Methanol, 605g Ammonium Acetate.
Slowly added 82g Sodium Cyanoborohydride.
Maintaned pH at around 6-7 with concen. HCl.
Added some silica gel to keep water out of reaction
(promote better imine formation).
Kept stirring for about 3 days.
---
Evaporated off methanol.
Added HCl till pH 1-2.
Extracted off unreacted ketone with DCM.
Added cold NaOH till pH was around 10-11.
Color changed to a lightish brownish with some weird waxy
looking precipitate floating around. No amber oil was seen
even after letting sit in ice bath for 1 hour.
Continued with DCM extraction to get freebase...
Boiled off DCM, a very small amount of oil was seen.
Turned freebase into HCl salt.
Yield was around 4%!! That is four percent, very low!
Some extra info:
The sodium cyanoborohydride was fresh, SWIM has little
reason to believe that it was inactive.
SWIM didnt put N2 inert atmosphere when reacting for 3
days, but come on guys... That would not inpact yield to
4% !! SWIM expected at least 40% and up!
SWIM wonders if the ketone was in fact the ketone? Like
SWIM said, it smelled nothing like safrole. Had that
definate smell of ketone. What else can it have been
anyway?
There wasnt much unreacted ketone leftover from DCM
extraction after reduction. Leads SWIM to believe that
something must have been formed! Is it still in solution
after pH is brought to 10-11? For the hell of it SWIM put
it to almost 14 after just to see, nadda.
Is there a better method for taking that freebase oil out
of solution? Keeping it in fridge 24hours didnt help. Is
NaOH solvating the MDA? Could SWIM have used bicarbonate
to get it out?
SWIM tried this 4 times. Same results!
SWIM has been searching on hive for a while now, no posts
people have put seem to give SWIM any ideas.
Any help would be appreciated, thanks in advance.