09-03-02 01:00
No 351987
Is it worthwhile to try and save the Methylamine produced in the standard Al/Hg Nitromethane reduction? Was thinking of adding inlet adapter and hose to 3 neck reaction flask and bubbling into ice cold dH2O.
If they drive God from the earth, we shall shelter Him underground - Dostoevsky
(Master Whacker)
09-03-02 02:30
No 352015
It would probably be a waste of time to try to recover the small amounts of MeAm which escape from this reaction unless you have a serious amount of spare time on your hands. Although the fact that you are considering using methylamine in place of nitro in the reductive amination shows that you are realizing that methylamine really is the only way to go.
(Hive Addict)
09-03-02 07:06
No 352123
MeAm is definatly the only way to go with anything above 500gms of ketone. It is not at all hard to do. Just run a hose from you rxn vessel to a beaker of Dilute HCL during the basification of the post rxn mix. This will also keep the lab Fish free. You could calculate the ammount of MeAm you need for a rxn and use only enough hcl to make a 40%aq solution of MeAm*HCL. then use it directly in an osmium al/hg. definatly worth the extra tube. Even if it only got rid of the smell. keep in mind too that there is alot of MeAm going to be left over in a proper rxn. In a rxn with 1 mole of tone theoriticaly there should be 3 moles of MeAm so that leaves 2 moles to recover and use again. If you are letting it just vent out it is going to waste
So much game I could sell a hooker some pussy
Vl_
(Master Whacker)
09-03-02 08:45
No 352165
"In a rxn with 1 mole of tone theoriticaly there should be 3 moles of MeAm so that leaves 2 moles to recover and use again. If you are letting it just vent out it is going to waste"
If the reduction is run properly, the great majority of the extra 2 mols of MeAm will stay solvated in the alcohol. A wet towel placed over the openings to the atmosphere is enough to absorb any escaping vapors. As long as the reaction is kept in the appropriate temp range, release of amine vapor is minimal.
(Hive Addict)
09-03-02 19:45
No 352313
I was refering to the release during post rxn basification. usually heats up enough to spew it all out. this is good though. It keeps the possibility of having MeAm in the first crop low. Swim has a special vactrap built and actually sucks all his MeAm for collection. The MeAm ain't too soluble after it's been basified. Is it proper to cool the mix whilst basifying?
VL_
VL_
So much game I could sell a hooker some pussy
Vl_
(Hive Bee)
09-04-02 15:57
No 352591
of Producing Methylamine? I've been put off so far from making my own because all the common formulas seem a pain to run and clean up the methylamine.
Anyone have a good recipie for making it from Nitromethane?
If they drive God from the earth, we shall shelter Him underground - Dostoevsky
(Hive Bee)
09-04-02 16:10
No 352593
Hydrogen and a litte Pt or Pd is very clean and quick.
(Hive Bee)
09-05-02 11:23
No 352953
Go about it the same exact way you would if you were to do the MM al/hg, just don't add the mdp2p. I have never done this, but I read that it was an option. Distill the alchohol which contains the MeAm, acidify, then evap the alcohol.
& I'm, somethin of a phenom, 1 puff of da cron, I'm un-stopable.
(Stoni's sexual toy)
09-17-02 17:35
No 357309
Once you're done with the Al/Hg reductive amination of ketone, filter out the Al sludge (as opposed to basifying with shitloads of NaOH). Then remove the alcohol by distillation. Since the Al/Hg using MeNH2 instead of nitromethane requires much less solvent it isn't that much alcohol you have to distill. A rotovap will allow you to do this pretty quick, without having to wait for hours.
The distillate will have a strong smell of MeNH2 and can be reused in your next Al/Hg reaction. You can also neutralise the solvent with HCl and evap/distill the alcohol again and dry the residue in a desiccator if you want to produce solid methylamine hydrochloride.
I'm not fat just horizontally disproportionate.
(Title on BackOrder)
09-18-02 02:43
No 357501
You always have some really good ideas on improvements for methods. Filtering the aluminum is a much better way of doing things. I never thought about distilling off the methanol for reclaiming though; that methylamine containing methanol would be good to use for the next reductive amination. Just add some more nitromethane as well to keep the ratio of methylamine to ketone up.
All paths are the same: they lead nowhere