NeoSynthesis (Hive Bee)
10-13-03 07:32
No 464416
      MeAm Synth = TOTAL FAILURE :(((  Bookmark   

SWIM tried to dream up some MeAm from synths posted on the hive.

Dream consisted of:

100.12g/Paraformaldehyde
124.40g/Ammonium Chloride
165.78g/dH2O

Mixtre was combined in a 1L 2N RBF in a simple distillation setup and heated over a water bath.

@ around 60C everything disolved & the mixture became clear (homogenous). Heat was maintained in a hope of hitting the desired 104C & keeping it there for the required 4 hours or so. Only here's the thing: The water bath started to boil away and rxn temp sort of peaked @ around 96C! This did sort of cross my mind before the dream... I mean how can you heat to 104C in a water bath (water having a bp of 100C!)?

In this dream I was following 2 synths. The first was Shulgin that states to use a "steam bath" (me not knowing wtf that is I figured water was close enough), and Raffik which doesn't say what he used to heat the soln (looked like a mantle to me anyways).

Regardless here's my problem:

1. Assuming I fucked up on the water bath part, and that an oil bath should be used, do I just let the fucking thing reflux for the desired 4 hours? If that's the case.. I guess it would be wrong to use a distillation setup, since all the water would boil away! Wouldn't a reflux be more appropriate?

2. Assuming paraformaldehyde isn't good for this synth (G-d knows why!?), what does regular 37% formaldehyde soln have that mine didn't, that would allow the soln to maintain 104C without boiling away?

Looking.. hoping... praying...

thanks beez!

Peace -



Ahem: (revelation) Unless of course something about the para & NH4Cl that are dissolved in the water would for some reason bring up it's bp??

Houston.................????
 
 
 
 
    cublium
(Stranger)
10-13-03 08:04
No 464419
      Raf used a mantle IMO(check these pics on...  Bookmark   

Raf used a mantle IMO(check these pics on rhodium site),it's not possible to use water in heating bath,if you must use a bath,fill it with vegetable oil.

Ahem: (revelation) Unless of course something about the para & NH4Cl that are dissolved in the water would for some reason bring up it's bp??



These substances when dissolved in water,in certain amounts,raise the boiling point of water to about 120 C,in my experiences they do anyways.

 
 
 
 
    NeoSynthesis
(Hive Bee)
10-13-03 08:44
No 464424
      Evidently...  Bookmark   

Well.. in SWIM's dream, the above rxn mixture was switched to an oil bath. Temp wasn't watched for a bit & shot up to 114C. Heat was turned off in order to allow soln to cool down to 104C at which point low heat will be applied to maintain that.

Small amount of distillat came over. I guess you were right about the Bp of water being pushed up! Pretty much all of it is still in the soln.

Will maintain 104C for the required 4 hours, then will follow BS's writeup. Seems much more concise.

Oh.. SWIM does NOT have vac filtration apparatus. ANY IDEAS WOULD BE REALLY REALLY APPRECIATED!

Thanks Beez,

Peace -

Houston................????????????
 
 
 
 
    NeoSynthesis
(Hive Bee)
10-13-03 09:25
No 464432
      A second revelation?  Bookmark   

Another thing about this MeAm synth...

I re-read (and compared) both BS's & Raffik's write ups and have a couple of question. The procedure seems to call for the following:

- After the 4 hours @ 104C the reaction is deemed "complete". Crank up the heat to distill off "half the contents" (i'm assuming this is reffering to water) of the rxn flask.

- Allow the rxn flask to cool down to r/t and to filter off the NH4Cl that precipitate out of soln.

- Return rxn flask to heating bath & vaccum distill the remainder of the solution until a mass of crystals evolves. This mass is said to be 98% MeAm.HCl.

As for my questions:

1. How do you know that you got all of the (excess) NH4Cl when you only evap'd half the water of the rxn flask?

2. I realize that the NH4Cl will come out of soln because it's probably not very soluble in water. Is there a way to predict how much excess NH4Cl you should have, so that you know if you got it all out?

3. Why not return the rxn flask to the heating bath after the first NH4Cl filtration, heat it some more & see if more NH4Cl precipitate?

4. After having filtered off (let's say) all of the NH4Cl, the writeup calls for vacuum distillation until nothing more comes off, then to cool the rxn flask & watch the MeAm xtals appear. Do you then simply pour in some Chlorofom, heat it, let the MeAm xtals disolve, filter out whatever didn't dissolve, cool & vacuum filter the MeAm xtals?

5. Will any remaining NH4Cl remain solid in chloroform?

I know this is probably a pain to answer.. But even short answers to the above would be appreciated. I plan on making a step-by-step photo writeup of the MeAm synth after it's been perfected.

Thanks - Peace out

Houston.......................????????????????????
 
 
 
 
    bio
(Stranger)
10-13-03 13:06
No 464472
      Good Grief  Bookmark   

This reaction has already been perfected decades ago. Follow the procedure in Organic Synthesis (Rhodium has a link) it answers all these questions.
 
 
 
 
    NeoSynthesis
(Hive Bee)
10-13-03 19:46
No 464518
      I want to die....  Bookmark   

Now I know how napoleon felt when he lost the war against the russians..

failure.. seems like my life story. This bee's about to cash in the stinger.

Here's my sad tale:

100.12g/Paraformaldehyde
124.40g/Ammonium Chloride
165.78g/dH2O

was combined in a 1L 2N RBF in a simple distillation setup and heated over oil.  Took me almost all day until i finaly got the temp stable at around 106C. Kept it there for the 4 hours (even a bit more), then pulled the flask out of the bath, chilled it in an ice water bath, filtered out the NH4Cl precipitate (chunky white powder substance.. no clue why folks call it "crystals"), and put it back in the oil bath.

Cranked up the heat till half the soln (or thereabouts) evap'd out. Then took it out again, for a second chilling, only this time like 98% of the soln turned into fucking NH4Cl precipitate!!!

I'm steering blindly here.

This is the NEWBEE forum. I've posted and posted and posted and all i fucking get is UTFSE. Well guess fucking what??? I've been doing nothing but that!! I've got every post on the subject practically memorized, not to mention printed, highlighted, and underlined. I may not be a genius like some of the more experienced beez come accross, but i'm not brain dead either. Most of the write ups on the MeAm synthesis aren't newbee material. They take for granted that you know a lot more then you might in reality. I had to cross reference between Shulgin, BS & Raffik to try & fill the gaps between steps. Supposedly it's all the same synth, but try and pull it off!

Anyways.. enough self pity. If anyone CARES to help me out, I'd appreciate it. If you're looking to stroke your ego by flaming me, do us both a favor and move on to the next fucking post. I've had all the knowledge flaunted in my face that I can take. I'm so fucking devastated over this failure I don't need more crap poured on my head.

Hope no bee has to go through feeling like this..

Peace -

Just fucking shoot me
 
 
 
 
    cublium
(Newbee)
10-13-03 21:25
No 464532
      Did you try to filter that 98% NH4Cl mix?  Bookmark   

Did you try to filter that 98% NH4Cl mix?Cub always got nearly tootpaste-like mix when cooled down,just filtered to get most liquid and proceeded