Yellow smoke

[Grignard]

When mixing the RP and I2 the rxn get some out of hand and there was evolving yellow smoke from the bottle.. I thencool the bottle and added the rest of the precursor.. After the reaction had slowed down i added the ephendrine.. Would this yellow smoke formation fuck up the reaction??

[fuse]

FuseSays 'highly doubtful'. Now im not exactly the most versed in these matters.. But i believe, had the smoke been a darker color, (reddish, dark yellow/brown, something along these lines) that you might have had some problems, or the ever fabled flask fire. again.. im not anywhere near being an established 'fast food chef' (cough cough). but utfse man. or hit rhodiums site and study.

p's

[biotechdude]

When mixing the RP and I2 the rxn get some out of hand and there was evolving yellow smoke from the bottle

What is produced when you react RP + I2 -- heat --> mmm, HI perhaps!!?? (u may wish to look up its appearance properties)

If you had ALOT of the yellow HI(g) escape (esp in nano rxns), you may have lost TOO much so that the HI concentration will never re-reach the required 57%(aq). 

Swix's guess is that you heated the rxn up too quickly and ran it too dry.  This meant your quickly-evolving HI couldn't be condensed or absorbed into the water fast enough and hence made its nearest escape route out of the reaction vessel and into the neighbours nostrils...

[Grignard]

He he... not god! There was smoking a lot, but i followed the right ratios, but it was only the half of the iodine, the rest was put in on a controlled manner.. I added 25g ephendrine after this had happend and the reaction boils about 110-115C What can i do to get the HI consentration higher? Could i put in some more rp and I2??  

[Osmium]

You might wanna try to add some water. Or read the sticky thread. Or use the fucking search engine.

I cannot believe it. Do you people even do the slightest bit of research before you chuck everything together?

[Grignard]

Im not so familiar with this meth syntheses.. thats not what i do for a living!

[wareami]

to what osmium is saying! Understanding what you are about to undertake shaves many aggravating hours off fixing stuff when it goes wrong.
The problem here with the excess smoke occurred because half the I2 was added to begin with.
The excess RP reacted unfavorably with the I2 present.
If making HI before adding the E...then there is no need for incremental additions of the precursors.
Just throw it all together with the dh2o and heat til HI is UP to Snuff then add E!

[Grignard]

So the reaction is just fine then.. I opened the rx bottle and white HI react with the moisture in the air... so i think everything is just ok then..    thanks for the help..

[geezmeister]

The reaction would have been fine IF you also added water. This reaction needs water. You didn't give it any. You opened it up to the air so it would "absorb moisture." Of course, since there was no water to hold the HI you had produced, the HI escaped. You likely have too low a concentration of HI, and at the water level and heat you are cooking, should have some fine tweaker medicine. Sparks and all.

Maybe a little meth to go along with it. And LOTS of intermediates and by products.

This is not, IMHO, the way to do this synth at all.

[JUMPER]

Osmium, just to answer your question as far as JUMPER was concerned, he had heard it was foolproof. So he just threw everything together with bits of info and his ego and let it fly! It wasn't until he came running with questions during RXN and got the shit kicked out of his ego not once, but twice, that his brain kicked in and started reading like he was told. Still have stomped ego stains in the so-called lab.

   BAD JUMPER! BAD JUMPER! Over the months I have definitely seen that I am not alone in this fucked up way of thinking. If everyone knew how cruel you mods can be.

[Grignard]

!!!! of course i added water!! 30 ml.. I just mean that the reaction are going and HI are given of.. So this must be a sign that everything is ok?, i have refluxed the shit about 20 h.. and i will cook it 20h more..

[geezmeister]

WHEN did you add the water? and how much water, red P and I2 did you add? If you added 30 ml to a proper ratio of I2 and redP you should not have seen that much smoking.

[Grignard]

I followed your ratio 1:1,2:0,5:0,8... E:I:P:H2O.. First the water, then i added the P and then i added the I, and when half of the I2 was added The reaction got a little out of hand.. The water was room temp.. But i imideatly put the flask in cold water and the rxn slowed down, then i added the rest of the I and waited about 10 min before i added the eph. But everything looks nice now. Do you think the HI is to weak?? .. I didnt do this in a fume hood, so you could figure how this was , But next time i will do it with proper ventilation at least..

[geezmeister]

At those ratios, it sounds good to me. I am surprised that you had a smoky start. Did you mix the water and redP and add the I2 in portions, or just dump everything together?

[Grignard]

That was the problem i think.. First i addes the water and all the P. Then i start to add I2 with a spoon.. But it might have been bether to add the I2 first then the p, because the P was in a wery high ratio to I2 when i first added it so the hole thing ended upp in a chain reaction.. But now i know.. he he.. Always add the I2 first since it is this component that makes the HI gas..    But do you think this is significant for the yield? I think i got a good HI, but the rxn mixture looks exactly the same as the one i started with.. Put my nose over the condensor and there is HI in there..  ! But i dunt smell the meth..

[geezmeister]

Give it time at the right temperature. You will smell the meth.

You made the HI then added the pseudo, which many tout as the way to go. I do this when I make the HI from phos acid or from hypophosphorous acid. I never found an advantage to doing so when doing a LWR with pseudo. When I start a LWR with pseudo I combine the pseudo, the red phos and water and mix until I have a homogeneous mixture. I will even heat a little in the microwave to get the mixture the way I want it. I then add the I2, sometimes in portions, and swirl it as I do, mixing the I2 in. With the wet mixture, I do not have problems with smoke evolving at the start, and the amount of water I have present in the solution keeps the HI production from taking place so fast that byproduct formation becomes a problem.

If I were making the HI before adding the pseudo, I would be inclined to mix the red and water into a slurry and add it to the I2 in the flask, cap it and let it produce its HI, let it cool, then add the pseudo.

There was a time I considered the smoke at the start a sign of success. I now consider it a sign that I screwed up at the start. I don't need smoke, or mirrors for that matter. I just need the HI to be absorbed by the water so it will be available to do what I need it to do.

Do cook that reaction 36-48 hours, and do get the temp inside that flask up to just under 100C at least. You can go a little hotter than that with a wet start or if you produce the HI first then add the pseudo or E. IMHO the magic temp seems to be about 95C, and the reaction thrives for the next twenty degrees C to your benefit. Hotter than that and your court some risks to the product; lower and you risk yield losses. In my experience.

Actual mileage may vary depending on driver.

[CharlieBigpotato]

swim agrees w/ geez, as usual, and would add that, when using fb precursor in a lwr, it may bee prudent to beegin on ice, and let things evolve very gradually, to avoid that sudden exothermia.

swim has always dreamt of tossing it all in cold; covering it once and only once. problems in the order of adding ingrediants have been about texture, more than anything else.
sometimes, one dreams of unmixed crud getting stuck on the sides of the flask beefore it's all mixed well, and staying there for 24 hours or more. which is worth avoiding, especially in nano rxns.

which leads me to this possibly stupid question, which may have been covered beefore, but i can't utfse, beecause of painfully slow connection and out-back phone service:

when doing a free-base rxn, might it bee good to add the freebase in a solution with an np? this would keep it as a liquid, hopefully, until after the exothermia of HI formation, so that it needn't suffer the added exothermia of the acid/base rxn until after the np had evaporated.

or maybee the np could remain in there all along without harming things? keeping it all more slippery?

thanks for feedback