This is a little bit off topic but this thread has been kind of dead now for abit and in the aid of cleanliness this is the best place for it.

Has anyone ever tried to perform the Goldman reaction using bromosafrole? Is there any reason why it would not work? It shows 82% yeilds in 2 hours and seems simple as hell so if you could would someone show me why this wont work. I am also abit confused as to the CuO since normally CuI is used to the best of my knowledge.

ok you added the amine dropwise when you should have it in the mix before you add the iodosafrole because believe it or not the reaction takes place pretty quick.
also, i noticed you did'nt check the ph of the aqueous phase before extracting with toulene and you only did one extraction.
the official reason these reactions are done in alcohols and not polar aprotics is explained in j. march's advanced oragnic chemistry.
i'll see if i can find the explanation but it sounds something like this.
methylamine is a strong nucleophile and can react in alcohols, the only time you use soovents like dmf is when you have a weak nucleaophile and it contains an anion.
the solvent  in this case energizes the nu by solvent effect.
for example the negative poles surround the cation and "cage" them the anion now is a stronger nucleophile or something like that
it's pretty early.
i'll explain more.

sounds to me your yeild was low because you made a lot of qauternery ammonium salts.
5 moles will give you something but not much.
and yes 8 moles is bare bones minimum and that's after i account for loss during the gassing of the alcohol because i tare the alcohol and the weight of the vessel and then weigh it after all the amine is bubbled through to calculate the mole number methylamine in order to know how much iodosafrole to add.
depending on it's concentration the reaction occurs rapidly in minutes.

I didn't understand the mecanism you were trying to explain ( I still don't know if you are talking about SN1 or SN2) but here is a trial with methylamine SN on iodosafrole in isopropanol:

_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*

150 ml isopropanol is poured into 250 ml RBF fitted with a thermometer. The RBF was previously dried in an oven and flushed with nitrogen. The RBF containing iPrOH is closed with a stopper and put in the freezer. When the isopropanol has been cooled down to -10 the flask is placed in an ice bath. Meanwhile 50g of anhydrous NaOH pearls are placed in another RBF fitted with a dropping funnel containing 35ml (15+ eq) of 40% aqueous methyamine. The methylamine solution is added dropwise and the gas is carried with a glasspipe through the  cold isopropanol. Methylamine is very soluble in cold isopropanol. At the end of the addition the NaOH solution is slightly heated to let evaporate the rest of the methylamine. 5g of iodosafrole as green needles (melts at RT to give brown oil) is added with a pipette to the isopropanol/methylamine solution. The flask is closed with a stopper and the solution is stirred for 3 days.

Then the brown solution is basified, rotavapored with the help of gas washing flask containing 5% aqueous H2SO4 to avoid filling the lab with  fishy fragances. The brown residue is acidified, washed with 2x50ml toluene, Basified with NaOH 2M and extracted with 3x 50ml toluene. The oraganics extracts are combined , dried over MgSO4 and gassed with anhydrous HCl to give few mg of black amorphous "crystals". The result is not analysed and is considered as failed. yield = ~0%

Notes :

1) Methylamine gas was not very dry because is was not passed through a gas drying agent.
2) Isopropanol was dry.
3) The first toluene extracts were rotavapored to give a few grams of safrole-smelling oil (probably isosafrole)

@dongle
there is no need to explain any further it's a documented procedure, it works if the technique is correct.
what happens is somebody attempts a reaction once, maybe twice then assumes it does'nt work.
when in reality there is usually something done incorrectly during the process that causes it to fail.
i pointed out in the other thread(s) when someone has attempted and failed what was  done wrong.
just because someone gets a reaction wrong the first or second go around does'nt mean the chemistry is unsound.

yes because i said you have to bubble the methylamine into the alcohol.
the reaction does not like water at all.
also the salts should be yellow do'nt bother with stirring that.
so what you got was a lot of tar i see in the alkaline phase and some recovered isosafrole.
does the isosafrole have a spicy odor?
also if you really are paranoid, did you know they can lift prints from photos?
might want to crop that out.
also copper forms complexes with amines and ammonia so in the future avoid it when working with stuff like this.

Quote from: jon on November 01, 2010, 03:55:29 PM

also if you really are paranoid, did you know they can lift prints from photos?
might want to crop that out.

good call, in that pic i could see a perfect fingerprint as well.  blur that shit out or crop it or something.  next time wear gloves just to be on the safe side.

AMEN!!

copper likes to complex with amines/ammonia or as cagney would say "you dirty copper!"

i did say that too my mistake

Thanks for the input guys.  A boneheaded mistake on my behalf and I'll definitely keep it in mind in the future.  Pics will be back up after they've been "cleaned".  So would it be better to use say... galvanized steel with the zinc coating stripped in Muriatic Acid?  I galvanized a section of pipe and it just seems too damn dirty even after scrubbing with steel wool multiple times.  I have looked around many places for SS pipe and can only seem to find the zinc plated stuff.  

Can anybody elaborate on the fire extinguisher vessel which was mentioned earlier in this thread?  Can't seem to find much info but it seems like a much cleaner way to perform the reaction..

Thanks for the input guys.  A boneheaded mistake on my behalf and I'll definitely keep it in mind in the future.  Pics will be back up after they've been "cleaned".  So would it be better to use say... galvanized steel with the zinc coating stripped in Muriatic Acid?  I galvanized a section of pipe and it just seems too damn dirty even after scrubbing with steel wool multiple times.  I have looked around many places for SS pipe and can only seem to find the zinc plated stuff.  

Can anybody elaborate on the fire extinguisher vessel which was mentioned earlier in this thread?  Can't seem to find much info but it seems like a much cleaner way to perform the reaction..

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Stainless Steal Kegs.

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