You dont have to be a hen to know how to make a tasty omelette.
- obviously some bees would like to be a chicken though; I just thought I could supply them with info on how to become one...
Not all NH4Cl goes into solution at once but dissolves whilst heating up/during the reactionAnd sometimes, it goes completely into solution at once, but partly precipitates upon applying heat...
But you're right; the outlines for a successfull procedure were given long before in this thread - I just wanted to throw into discussion a few new thoughts about ratios, molarities etc. to provide thought food to those trying to find a mechanism that explains why alcohol is helpful (some bees are not content with knowing that it works nice but also want to know why it does - or maybe better said they want to know why they don't get good results?)
I could still think of *several* ways of varying the rxn parameters to learn more about possible mechanisms and stuff; but as you said, the outlines for a successful application of the patent were given, and it is up to everyone to make his own guesses about why it works the way it does.
Just thought I could help in doing so by providing more data (its always better to start from experimental data rather than from speculations when trying to find out about rxn mechanisms
) - but as you think it isn't necessary...
Not to piss you off armer-geddon I share my most private experiences here with you... .
COOL DOWN!Probably you're right with that as well
- well supervising a rxn for >12h isn't that exciting; so I tried to get some diversion by bragging about how it could possibly work - I still think my theory has some right points in it...
About the workup - I advise to use the following procedure:
after concentrating the remainder (orange syrup) to dryness and letting it cool/solidify, add small amount of IPA, crush up solid cake and decant IPA (save it). This contains methylamine HCl and most of the orange impurities.
Now add some 300ml IPA (for 200g hexamine used in the beginning) and reflux it for 30 minutes, then decant the IPA into other beaker and let slowly let cool to -7°C, filter precipitated MeAm crystals, rinse them with acetone, chloroform and again acetone, let dry for a short time and place in sealable container. The washes will form a 2-layer system in filtering flask - clear upper layer acetone and red bottom layer CHCl3.
Now place the mother liquor (without the washes!) into your flask with MeAm/NH4Cl-cake again, and reflux again for 30 minutes, then repeat the decanting/cooling/filtering/washing and add the so obtained crystals to the first crop. Repeat this 4-5x with same mother liquor, then extract one last time with small amount of fresh IPA.
Combine the small first, dirty extract with the remaining mother liquor and final IPA rinse and concentrate under vacuum, then cool, filter and rinse with tone/ChCl3. Recrystallize from ~250ml boiling IPA per 50g of raw product to get clear, colorless crystals of good purity.
The good thing is that you only have to deal with dirt and byproducts (by thoroughly washing/crushing up inside funnel) when crystallizing the contents of the first small extraction; the following xtractions (using same mother liquor) will contain substantially less impurities and result in clean crystallization of the product - but will account for the major amount of isolated MeAm...
A