posted 09-23-1999 01:33 AM         

By doing this, it is said that you can avoid many of the byproducts, (such as azridine)

"the acid is prepared first and allowed to come to a complete reaction for 20 min before adding the ephed."

Another option was to prepare it by
reacting 300g of I w/ 30g of RP in 300mls
of water, then distilling off the first 2/3
for use.

Obviously this requires more work, but should there not be a payoff for that extra work, when compared to other options such as the push/pull in terms of overall quaility
of the end product produced.

posted 02-09-2000 07:23 PM         

prickleberry
Member posted 08-07-99 04:44 PM
--------------------------------------------------------------------------------
Lesson 1; HI acid.
The stinky way.
I2(aq) + H2S(g) ---> 2HI(aq) + S(s)
H2S can be made by reacting FeS and dilute HCl, and bubbling the H2S gas into the I2 solution, but this method can be dangerous or fatal if gasses are inhaled.

OR

Combining the elements and bubbling into water. Done at about 200C in the gas phase with a catylist such as Pt.
I2 + H2 --> 2HI.

OR

Hey-Mans method.
2NaI + H3PO4 -->2HI + Na2HPO4 and bubbling the gas into water.

OR

Red Phosphorous method:
2P + 3(I2) + 6H2O --> 6HI + 2(H3PO3)
The hard part here is getting the Red P.

OR

Hypophosphorous acid method.
H3PO2 + I2 + H20 --> H3PO3 + 2HI,

OR

Tetralin may work, but you'll haveto look that up yourself.

OR

Sodium Bisulfite (NaHSO3) is said to work by some, and goes something like this...

NaHSO3 + NaI + --> HI + Na2SO3
Better check that rxn.

Keep checking for lesson #2. If any mistakes are found, please point them out in a constructive manner.

posted 02-09-2000 08:21 PM         

Side reaction PH3 + HI ==>> PH4I

posted 02-10-2000 01:50 PM         

HCl + NaI -> NaCl + HI

With sulfuric acid:

H2SO4 + 2 NaI -> Na2SO4 + 2 HI

However, these two salts are soluble in water and thus hard to remove. Na2SO4 is not very soluble, however. It might be possible to remove it by cooling the solution down to the freezing point and filtering, but this won't quite remove all of it. I don't believe that leaving the salts in solution will create a problem, but I am not entirely positive.

Perhaps someone with a better understanding of hydriotic reductions can verify this?

posted 02-11-2000 05:03 AM         

--------do not answer cause I'm searchin-----

So you mix yur acid with yur E and then jus simmer with the lid on fur awile and yu geta the stuff. When do you add rp because you must need rp, otherwise Why was I fighting this dangerous and difficult task of aquiring rp. I nose dat I bee havin posphoric acid, I2, and lotsa E. there must be a catch???????........Or iva ben spinning me wheels.

-----If you feel you must repond to this question you can but do so at your own risk....---------

posted 02-11-2000 07:51 PM         

As Hematite said, "Refluxing Eph/P-eph in hydroiodic acid produces a product fully laden with toxic additives, and is not a rxn for the inexperienced." Aziridines and unreduced iodoeph are the main toxins