bromosafrole

[serodronin]

AFOAF was intending to make some Bromosafrole, but she believes that an aquatic solution of HBr will not produce good yields.  what other solvent can she use to hold HBr in approx. `+ soln?

[Osmium]

Post 22772

(Osmium: "Bromosafrole breakthrough?", Serious Chemistry)

[startinout]

Osmium is correct, it works as such, but in reply to your concern regarding yields one needs to weigh up benefits, even a 10% yield would be favourable when weighed against the benefits of purchasing and/or cost of materials.

'Isn't society irrational'


blue always
except for at the start

[serodronin]

10% yields would work for the amount of feed material ,my friend has, but she has read journals from chem. abstracts, JOC, JBC, JACS, JCs, etc. that all say 95-100% yields are possible if water is not contained in the reaction.  She likes the sound of this a lot more.  I think she will go with safrole dissolved in chloroform and then gas it with anhydrous HBr.

[psychokitty]

Kitty has never done it, but Ritter claims SWIM has performed the hydrobromination of safrole using Fester's method:  1 part acetic acid to 1 part safrole are mixed with an amount of 48% HBr (don't remember exactly how much but I do have Fester's book to refer to if need be).  This is cooled in an ice bath to about 10 deg C and cooling maintained while anhydrous HCl is gassed into the stirred mixture over a period of one hour.  The container is stoppered and allowed to stir for about 2 days or so.  Then, the whole sheebag is dumped into ice cold dH2O, and the rest of the work-up is standard.  BTW, the HCl dehydrates the HBr, liberating it to react with the safrole to form the desired bromosafrole. Yields are about 75% at a starting scale of about 100 g of safrole.

Although no one here really trusts most Fester methods, Ritter swears that this one is gold.  Good ventillation would be the only obstacle that I can think of as this method seems incredibly easy.  If you want the actual details, they MIGHT be on Rhodium's page.  If not, I can get the information for you.

Good luck.

--PK

[serodronin]

I think UF is confused about a lot of org. chem.  I read the articles that his information came from, and it claims that acidifying in AcOH with aqueous hydrohalogens causes polymerization.

[homunculus]

48% WILL work, HCl gassing does improve yields, but the tricky part is aminating.

[Stonium]

Osmium is correct

As usual.

Biased...who, ME?  

I think UF is confused about a lot of org. chem.

Think YOU might bee RIGHT about THAT.  

Stonium

On time is when I get there

[improv_chem]

Where was your friend gonna get the gaseous HBr? 
Any good ways to make HBr(g) from NaBr?



If it doesn't work, smash it and start over

[psychokitty]

I've heard that reacting the distilled bromosafrole with aqueous sodium azide in a biphasic mixture using PTC is a good way to get the intermediate azidosafrole, which then is reacted directly (after separation of the previous two phases) with an aqueous solution of sodium borohydride.  Separatation of phases followed by standard work-up yields VERY PURE MDA in about 50% yield as the free base.

No, kitty has not performed this reaction.  But some other bee has guaranteed kitty that SWIM has.

--PK

[serodronin]

NaBR or KBr in sulfuric acid will produce HBr gas.  if your sulfuric acid is anhydrous, your HBr will be anhydrous also.

[Osmium]

Sulfuric acid is an oxidiser and will probably oxidise some of the bromide to Br2.
What about phosphoric acid?

[psychokitty]

I have an old chemistry book that says that both NaBr and NaI can be dehydrated into the respective anhydrous hydrohalogenic acids but that the reaction is too slow for practical use.

--PK

[PolytheneSam]

What about this link on Rhodium's page?

http://rhodium.lycaeum.org/chemistry/halosafrole.txt

[serodronin]

UF mentions making halosafrole from isosafrole instead of safrole.  wouldn't using isosafrole as precursor attach the halogen at the first carbon from the ring instead of the second(where you want it)?

[Osmium]

I think it depends on the reaction mode, either you do it by forming radical intermediates or ionic. Could be wrong though.

[improv_chem]

Ok, there is obviously a number of bromosaf compounds that could be made.  What about that DMSO Method that SWIM tried?  I think that is what PolytheneSam is asking about...  It certainly DID NOT form the desired amine when swaped with Iodine and reacted in the delephine rxn!!  (Could have been the delephine's fault though)  Someone said it was a DiBromo compound?  Has anyone tried reacting the product of the DMSO rxn with NH3 or MeAm in a bomb??  If it is the real thing then you should get some product, right?  I think we need some kind of table of possible reactions of Safrole and isosafrole with HBr in various solvents so Bees can figure out what they are going to get from a rxn.
Are you sure about the HBr not being oxidized to Br2?  SWIM thought he saw some bromine when he dripped in the Sulfuric.
SWIM is going to investigate making HBr using various methods as soon as he is a little less busy with other matters....
SWIM will post anything interesting if nobody else does by then.


If it doesn't work, smash it and start over

[PolytheneSam]

Here's two patents on the subject:  2456316 and 3864115 (see example 1 on 2nd page).

[The_Animal]

Can DMSO be substituted for anything else?

Insert signature of your choice here

[improv_chem]

PolytheneSam:   put those patent #'s into Rodium's search engine--> Gonna check it out tonight when i print it.

Animal:  Do you mean what can you use instead of DMSO in the Bromo procedure or do you mean what else can you use DMSO for?

Just a thought:  The only problem i can see with the DMSO procedure is that there might be a side rxn because of the NaHSO4 present. 
The product that SWIM got smelt nice and looked good after washes even though SWIM used washed saf oil and not distilled stuff.  SWIM found that the oil looses about 20% of its weight after washing, does that mean that it's fairly pure safrole?  The oil is supposed to be about 80% safrole right?
The Bromo product smelt kinda sweet and was a suripy, translucent pink/yellow/orange liquid at room temp.
Who was it that reported a similar failure with the DMSO method.., mabe YelloJacket??  I can't remember, but if anyone made this stuff and tried to aminate with some method other than the delephine i would be very interested to hear your story.
SWIM tried this procedure a long time ago with NaI instead of NaBr, and got shit all. 
Made more stink too.  SWIM thought he fucked up the delephine, that's why he tried it a second time with NaBr.
SWIM thinks that the DMSO method doesn't work well with the NaI since a lot of I2 seemed to be produced..
Anyone else got any stories on this procedure???
Sweat dreams............

If it doesn't work, smash it and start over