Author Topic: hey guys... DrFeelGood: great pics...  (Read 6220 times)

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  • Guest
hey guys... DrFeelGood: great pics...
« on: August 19, 2004, 10:35:00 AM »
hey guys...

DrFeelGood: great pics... great write up... but swim has gotten the distillation of saf down pretty good.... tho i don't have friggin >96%... godamn... as for swim's saf.. it's not clear and colorless... it's rather bright clear yellow... wierd...

AC:  nono... the h2so4 bubbler goes after inline cacl2 drying tube and before the fb/np... NOT after (unless i misunderstood you :)

also.. this part:

you can then vacuum filter this and wash a few times with NP and re-gas it, repeat until nothing comes out of solution....

when u say wash a few times.. u mean the crystals right? and not the fb/np...??


  • Guest
yeah i was talking about the gassing aparatus,
« Reply #1 on: August 19, 2004, 02:06:00 PM »
yeah i was talking about the gassing aparatus, it goes
generator-->inline CaCl2-->conc sulp-->fb/NP
Thats what i meant anyway...

Yeah the crystals that come out of solution, you freeze it then vac filter, then with a little bit of the NP from the filter flask (or better yet a bit of fresh DRY np) to wash the crystal mass in the filter, this will wash down any fb that may be stuck in there and generally clean the crystals fairly well (but will not replace recrystalisation in any way shape or form).



  • Guest
hey guys... AC: i thought that's what you...
« Reply #2 on: August 20, 2004, 12:52:00 AM »
hey guys...

AC: i thought that's what you meant....  that seems to be the ideal method of ensuring perfectly dry hcl gas... need 2 bubblers tho... dang..

swim wants to try out the performic to get ketone.. seems to be a better method than the wacker... which everyone seems to hate?!?! however... don't like the fact that isso is needed... another step... doh!


  • Guest
He speaks..
« Reply #3 on: August 20, 2004, 02:00:00 AM »
h2so4 (98% comercial drain cleaner) and hcl (for cleaning  pavements/concrete) works a treat .

you know when you've got it, make you choke so best try and avoid that

about - 0.65 as bad as MeNh2 which is noxious at best


  • Guest
Sorry about delay.
« Reply #4 on: August 24, 2004, 01:23:00 AM »
Sorry about not getting back sooner but I had some things to take care of...but with regards to drying your newly formed Hcl gas...all you should need is to bubble your Hcl gas through say a 500ml flask partially filled with H2S04 (500ml flask, 2 hole stopper and gas in tube leading just below surface and gas out tube that just barely enters the stopper).  You do not need the calcium chloride at all, the H2S04 will completely and throughly dry your gas for quite some time before needing replacement.   Then once it does require replacement you can just use the old drying H2S04 for the reaction H2S04  (the one that you add to the salt to get your gas).  Good Luck and Bee safe.  Pyrex out ;-)


  • Guest
That's right...all you need is H2S04 bubbler...
« Reply #5 on: August 25, 2004, 01:20:00 AM »
That's right...all you need is H2S04 bubbler setup.  I wouldn't use drain cleaner though, unless it is colorless.  My friend tried that once when he didn't have any lab H2S04 and the color bled through into his toluene.


  • Guest
the color bled through into his toluene. How?
« Reply #6 on: August 25, 2004, 02:05:00 AM »
the color bled through into his toluene.
Was the colour carried with the HCl gas? weird....



  • Guest
dry salt, how much gas, and suckback
« Reply #7 on: September 03, 2004, 01:09:00 PM »
I know this is an old thread but I just read it and want to comment on three things.  BTW - this is my first post on the Hive (I'm so excited!). Homeslice talks about drying salt for 3 hours before dripping H2SO4 on it?  Is this for real? Anyone else do this?

Krazy89 asked something that bothered me because no one responded to it.  He asked, "How many drops of sulphuric is needed to gas a standard MM synth workup?  there is about 500ml of xylene/freebase."  I always assumed that the quantity of gas you need is greatly dependent on the number of molecules in the solution that would want to associate with an HCl molecule, and only slightly (if at all) dependent upon the total volume of non-polar.  If I am wrong, would someone please set me str8?

And Mr. Pyrex talks about two methods that can produce suckback but believes that dripping H2SO4 on salt will not.  Did I read this correctly?  In my experience this can give you suckback as well.  I thought suckback was whenever you stop generating gas (dripping), all of a sudden the pressure drops inside your gas generating vessel, and the way to avoid sucking non-polar back into your gas generating vessel is to make sure your gassing wand is out of your non-polar before you stop dripping.  Again if I am wrong, please correct me.  Thanks.


  • Guest
to RedCabbage, SWIM remembers a post from...
« Reply #8 on: September 03, 2004, 04:12:00 PM »
to RedCabbage,

SWIM remembers a post from Osmium, stated an easy way for getting the .HCl.

For X volume of freebase, mix it with 5*X volume of IPA. Drip dropwise of 37% HCl to the IPA mixture, check the PH for every few drops. Stop when it is slightly acidic, about pH 5 is ok, 2 is too much. Like what sir Labtop always says, get ready for some freebase, add them to the too acidic solution to bring up the pH.

To a 20*X volume of ice cold ether, put on stirrer, start adding the IPA solution dropwise. Keep on stirring for a few minutes after addition done. Filter the crystals. Remove the solvent to recover more crystals. Dry them to constant weight. Recrytallise using preferred solvent to get cleaner stuff, get the correct dosage then happy rolling. 8)

SWIM suspects using ice cold IPA would be good for this.


  • Guest
Drying NaCl ?
« Reply #9 on: September 03, 2004, 05:33:00 PM »
Seems rather silly and unecessary to dry the salt.  The H2SO4 has lots of water in it anyways.  SWIM's never had to dry it.
And yes you can get suckback with salt.  It's best if you can manage to have a little trap in the gas tube before it goes into your freebase solution so that if there is any suckback it won't get sucked back into the generating flask. Or you can just be really careful and not always keep the gassing tube in the receiver flask.  Although if you enough gassing you will eventually get some suckback on ocassion no matter how careful you are if you don't have a trap.  Also those fumes are pretty nasty when they go into the air.


  • Guest
Swims never experienced gassing with h2so4...
« Reply #10 on: September 04, 2004, 06:17:00 AM »
Swims never experienced suckback with h2so4 over nacl. But he has with damp nacl with 31%hcl with h2so4 dripped over that.
Swims read about drying salt which is probably excessive but fuck it. Its at least a 3 hour workup so start the oven right after basification.
Swim usually uses about 50ml of h2so4 over about 1/4 can of salt, not really measured at all. At first swim lets a good bit flood the nacl through the addition funnel, lets say he lets it open for about a second or 2. Its a good bit and the nacl foams up but as long as theres no hcl in there it wont get too vigorous, in swims experience.


  • Guest
It seems like Dr. FeelGood collected ...
« Reply #11 on: September 05, 2004, 03:26:00 AM »
It seems like Dr. FeelGood collected everything up to 140°C. Wouldn't you have to change the receiving flask once you get up to 135-140°C in order to obtain pure safrole? Or can you just get your oil bath to the temp that safrole distills at and then put your flask into the bath? Is that what he did?  ::)


  • Guest
To gas with murry or to not... that is the questio
« Reply #12 on: September 05, 2004, 10:39:00 AM »
The only reason I like to add murry to salt prior to dripping conc. H2SO4 is because it seems to give a little more uniformity (controllability). The reason I don't like it is because I'm not really sure what is going on.  I mean, if you nix the murry then what you have is 2NaCl + H2SO4 --> Na2SO4 + 2HCl, right?  But you can also get HCl gas without the salt, just with murry.  Then I am imagining that the H2SO4 loves the H2O so much it takes it from the murry, and then the murry thinks it is over-saturated (probably not the right word) with HCl and so that is released as gas. And the reason I don't like adding murry to the salt prior to dripping conc. H2SO4 is because I don't know which dynamic (probably not the right word) is dominant.  Does this make any sense to anyone?  If not, please correct me.  This has been driving me bugshit for too long.  Thanks.


  • Guest
Well in theory the reason for adding the ...
« Reply #13 on: September 07, 2004, 09:01:00 AM »
Well in theory the reason for adding the liquid Hcl to the NaCl prior to the addition or even during the addition of the H2S04 is that it will make the setup more volumetricly efficient.  Basically you will be generating Hcl from the combination of the NaCl and H2S04 and you will also be releasing Hcl gas from the dehydrating action of the H2S04 on the liquid Hcl.
  So if your only concern was to get as much Hcl gas from any given setup and took nothing else into account like suckback, then you'd likely end up going the route of using all three compounds instead of just two for gas generation.  But here the main concern isn't to generate the most volume possible, since you can easily generate plenty for almost all applications except very large scale (maybe pounds or something?) and do so with relatively small quantities of NaCl and H2S04.
  Here most would be best to balance efficiency with idiot-proofability and simplicity (no disrepect meant to anyone ;-)).  So the best solution for this balance is to simply use NaCl and mix with a small volume of H2S04 and run the generated gas through a drying container containing H2S04 and then to your gas dispersion apparatus.
  If you use this simple method you should never have to concern yourself with 'suckback'.  As this setup will continually generate positive gas pressure even after you've mixed all of the two components together and you would have expected the setup to complete its gas generation (well personal experience has shown it will do so for at least 3 hrs with a setup consisting of a 1000ml flat bottom florence flask reaction vessel filled approx. 1/3 with ordinary table salt and then a 10 dram container filled completely with technical grade H2S04 dropped into the bed of salt and closed and then mixed slowly) it might be rather slow generation once all the components are mixed throughly but it will stay positive pressure unless of course you open the reaction vessel.
  But when interupting or discontinuing a operational gassing setup you should always make the first step to remove the gas dispersion tube from your solvent otherwise you take the risk of cross-contamination of the different components.  And as a side note to those interested in industrial methods....according to a text that I came across a while back the industrial method for generating Hcl gas was to mix liquid H2S04 and liquid Hcl.  I would imagine their reason for going this route is that there would be minimal'd just end up with 'wet' H2S04 and this could be regenerated by heating this 'wet acid' hot enough to drive off excess moisture.   Pyrex out of explanations and almost out of gas ;-)