One pot synthesis of 4-methylaminorex

[Bandil]

All of the solvents and reactants are quite harmless, so there should be no reason this reaction can't be performed without a fumehood... The only smelly thing that can occur, is if you use to much cyanate, which will result in formed ammonia upon the acidification in the last reaction step.

Regards
Bandil

[drjuiceflow]

Hi Bandil. I was wondering if you could answer the following questions at your earliest convenience?

1. What is the temperature that you set the hot plate for the norephedrine/KOCN reflux?

How about when you add HCL?

How much sodium carbonate do you use to basify ?

Also if I use the exact amount of norephedrine, KOCN, and HCL that you used in the synthesis, will there be ammonia or other smells generated that I should worry about?

Also what brand/type of hotplate and reflux condensers did you use or recommend that someone could purchase for this transaction?

Sorry for all these questions. I will be very grateful if you take the time and answer them.

[Rhodium]

You set the temperature hot enough for the solution to reflux (i.e. boil). That should be 110-120°C for most hotplates.

When adding HCl, the solution should have cooled down to room temp or thereabouts.

You add enough sodium carbonate for the solution to become basic (no precise amount can be given, as this will vary). Check for pH >10 with universal pH paper.

Any hotplate with magnetic stirring will work here, my own favorite being

IKAMag

(http://www.ika.de/ika/owa/catalog.showBrowse?iProcess=&iGroup=188)



Any reflux condenser will do - UTFSE for "condenser choice"

[drjuiceflow]

Should I set up an oilbath and place the reaction flask in the oilbath, or place the reaction flask directly on the hotplate? I would assume oilbath will provide for more even heating of the contents of the flask?

[Rhodium]

I would assume oilbath will provide for more even heating of the contents of the flask?

Yes, that's the main point of using it. Uneven heating may lead to cracking of the glassware and subsequent product loss and/or injury.

[harry]

Rhodium said, in answering SS's question on whether "Benz + Nitromethane can produce the hydroxynitoalkan instead of the nitrostyrene" Rhodium said, "Yes, using sodium hydroxide as the base and quenching with dropwise addition of dilute acetic acid. It has been discussed before."

Could some fine bee who knows where this was discussed please point me to its location ? Ive done quite a bit of searching and cannot seem to find this reference.  

SWIM has a littre of both benz and nitro just waiting to blossom into PPA.  

edit: Found it ! Tanx anyways. For anyone with the same question the procedure can be found in Psychokitty's post No. 227281

[starlight]

you cannot make PPA using nitromethane. you would need nitroethane otherwise you end up with one too few carbon atoms.