Author Topic: Epoxidation using Performic. Buffered or Unbuffered?  (Read 919 times)

NeilPatrickHarris

  • Dominant Queen
  • ****
  • Posts: 274
Re: Epoxidation using Performic. Buffered or Unbuffered?
« Reply #60 on: December 27, 2011, 03:05:43 AM »
You can't use calcium chloride to dry toluene that has free base in it as it forms complexes with amines as documented in the attached abstract which was posted on the Hive about six months before it went offline ::)  It can be used to dry toluene that is going to be mixed with dry free base oil for gassing  ;)  Bases such as sodium hydroxide work well as drying agents for amines  8)

gotcha.  my friend used to use CaCl2 to dry his toluene after extracting/washing prior to gassing.  so he would use CaCl2 to dry his toluene that has the amine freebase in it.  he's much more knowledgeable in regards to chemistry than me and far more experienced as well so i was shocked to hear this from him.  i referenced a general article that mentioned CaCl2 absorbing and complexing with amines, he said he was aware of that but never had any problems.  i would expect his yields to be hindered since amine freebase would be absorbed by the CaCl2 but his yields were always really high.  at any rate, thanks again for the reply lugh.  i've seen general statements but it's always good to hear it from someone else and that's a nice reference you attached too.

Dr Tox:
if he puts a cold finger on top of his condenser and if he's using a west condenser for reflux and a lot of MeOH vapor is escaping - would you be concerned with the volume of MeOH vapor condensing into liquid by the efficiency of the cold finer cause the cold finger to clog with freshly condensed liquid?  kind of like how reflux condenser can choke.  i say that because i've had a hard time in the past finding a large cold finger for a reasonable price.

staying on topic with the insufficient refluxing problem - i've never known anyone first-hand to use a west condenser for reflux and i've never used a west condenser for anything before so i'm not familiar with what it's capable of.  but judged by the design of the west condenser from pictures i've seen i wouldn't think it'd make a very good reflux condenser, i'd assume it'd be better suited for distillations.  since i've never played around with a west condenser before i can't say for certain but i would consider getting a larger reflux condenser (the length of the condenser should be considered depending upon what scale you're running the al/hg at).  i would also recommend that the new, larger reflux condenser is of a different design that is more efficient for refluxing.  i use an allihn but i've always eyeballed the thought of using a friedrichs condenser for the al/hg reflux condenser due to its design.  that brings me to a question though - has anyone used a friedrichs condenser for a MeNO2 al/hg before?  the design of a friedrichs condenser is very reminiscent of cold finger-type of logic in regards to how its design condenses the vapor.  but i'm curious as to whether a friedrichs condenser would run the risk of choking (not having as much room for that volume of condensed liquid to return to the flask) versus, say an allihn - if both condensers were the same length?

this paragraph is just to explain the concept of using 2 condensers, how running the individually on different necks versus stacking them would have 2 different outcomes.  i'm not recommending that you use 2 condensers because if you plan to buy a new reflux condenser anyway you might as well get one that is large and efficient enough to where you don't need a 2nd condenser.  but if you ever scale up larger than that new reflux condenser can handle then at that point you can always consider adding a 2nd condenser to increase your refluxing capabilities.  so in regards to using 2 condensers, if you were to do this then don't stack them like a lot of posts by bees in the hive archives have done.  by stacking condensers you're just basically achieving having one really long condenser which is great for now allowing MeOH to escape.  but this reaction is so vigorous that it's not uncommon for the reflux condenser to "choke" because the amount of MeOH vapor is so much that when it goes up into the reflux condenser and is condensed back to liquid, there is too much liquid and that condensed MeOH in liquid form is stuck in place where it condensed due to more additional MeOH vapors underneath it.  the reflux condenser is the only opening for the reaction flask to be exposed to atmospheric pressure, so if the condenser "chokes" then nothing will be able to escape past that MeOH liquid that's stuck gurgling/choking in the reflux condenser, put that in combination with the additional MeOH vapor being produced constantly by this highly exothermic reaction and pressure will rise in the reaction flask.  my reflux condenser isn't big enough to handle some of the larger al/hg's i've done in the past so i'd have a choking condenser guaranteed for those larger reactions, but i always used a 3-neck RBF.  reflux condenser in the middle, addition funnel with ketone/MeNO2/MeOH in a side neck, and a stopper in the other side neck.  so i'd unstopper the side neck briefly to allow pressure to equalize in the reaction flask and stop the condenser from choking.  then i'd immediately re-stopper that neck so the MeOH/methylamine gas would not escape from that neck.  problem is, within moments the condenser would choke again because my condenser was just not big enough to handle that much volume/capacity of vapor condensation.  the reason i recommend using 2 condensers is because you increase the capacity of vapors that can be condensed by using a setup like that.  with a 3-neck flask, an addition funnel on one neck, and a condenser on another neck, and a condenser on the remaining neck.  picture just having one condenser, all the MeOH that is being vaporized only has one way to go - through that one reflux condenser.  the longer the reflux condenser is, the lesser the chance of the vapors escaping from the condenser as long as its being cooled efficiently, however this doesn't increase the volume/capacity of vapors that can be condensed.  whether you use one condenser or 2 condensers stacked as 1 really long one, it can choke just as easily because there's not enough width to handle that much volume of condensed MeOH flowing back down the condenser and back into the reaction flask.  but if you have 2 reflux condensers, one condenser on one neck of the flask and the other condenser on another neck on the flask - now the MeOH vapor has 2 places to go.  so you just doubled the capacity of MeOH that can be condensed to solve the choking problem.  another solution is to just buy another reflux condenser of an efficient design that is just a big-badass, tall AND wide condenser.  but to be perfectly honest, once you get the feel of the al/hg down you only need one condenser.  just get a larger condenser with a more efficient design for refluxing and you'll be fine.

Wizard X

  • Lord of the Realms
  • Foundress Queen
  • *****
  • Posts: 1,224
Re: Epoxidation using Performic. Buffered or Unbuffered?
« Reply #61 on: December 27, 2011, 04:24:02 AM »
Hasn't anyone ever tried using metallic sodium to dry non polars?

Vogel has for both polar & non polar solvents. Solvent properties. http://en.wikipedia.org/wiki/Solvent

The Methylamine Complexes of the Rare Earth (III) Chlorides. http://pubs.acs.org/doi/abs/10.1021/ja01609a009
Complexes of the Ethylamines with the Halides of Calcium, Cobalt(II), and Zinc. http://pubs.acs.org/doi/abs/10.1021/ic50003a004#
http://bookdome.com/science/Modern-Chemistry/Salts-Of-Complex-Amines.html
« Last Edit: December 27, 2011, 04:50:11 AM by Wizard X »
Albert Einstein - "Great ideas often receive violent opposition from mediocre minds."

thescientist3000

  • Pupae
  • **
  • Posts: 50
Re: Epoxidation using Performic. Buffered or Unbuffered?
« Reply #62 on: December 27, 2011, 08:23:36 AM »
Hey Tox and Neil

The removal of the condensor and placing back on shortly is a sound tip.  It may have been done, but in a different situation than Neil's, it did indeed stop the choking.  This was towards the end of the rxn though. 

The idea of the friedrichs condensor looks interesting.  It appears to be a large version of the coldfinger, in that a coil is ran in both on the interior.  This could prove superior to the west condensor, if the area for gaseous flow is larger than that of the comparable West.  It also looks cooler 8)

Neil- As for drying the mgso4, oven treatment ensued.  400F for 2- 2.5 hours.  Went from clear crystalline rods, to white chalky powder.  High enough temp?

Cacl dryer will be added to hs2o4+nacl gasser.

Dr. Tox

  • In Stasis: See You In A Few Years!
  • Subordinate Wasp
  • ***
  • Posts: 145
Re: Epoxidation using Performic. Buffered or Unbuffered?
« Reply #63 on: December 27, 2011, 09:26:01 AM »
Just a couple random, drunken thoughts which is probably a mistake for me to be doing....

Friedrichs condensers are neat and all, if you can get one, why not? You may as well look for Snyders while you're at it....

Allihn configurations aren't bad either. Stack a layer of Raschigs at the bottom and top off with boro beads... .it's been done...

I, myself, have had spiral borosilicate internals break on inertial shock and while yes, this is solely my own fault, it happens. So, something to consider. Kind of like improperly using Claisens and the delicacy of vacc adapters.... Shit happens: blame gravity & mass.

Cold fingers are pretty damn solid. And get this, you can even make them via ghetto means for next to nothing, with soda bottles..... I'll elaborate if anyone gives a shit. A sort of bastardized DeWars.

Anyway, the important thing is that you get the feel for the process. You'll know by sight & feel where things are going and what you can or cannot do at a given time.

This is your adolescence leaving your body. Maturity lies ahead. Seize it.  8)
« Last Edit: December 27, 2011, 09:50:31 AM by Dr. Tox »
Alimentary, dear Watson; I had a gut feeling.

NeilPatrickHarris

  • Dominant Queen
  • ****
  • Posts: 274
Re: Epoxidation using Performic. Buffered or Unbuffered?
« Reply #64 on: December 27, 2011, 01:27:06 PM »
Just a couple random, drunken thoughts which is probably a mistake for me to be doing....

Friedrichs condensers are neat and all, if you can get one, why not? You may as well look for Snyders while you're at it....

Allihn configurations aren't bad either. Stack a layer of Raschigs at the bottom and top off with boro beads... .it's been done...

i always used an allihn for the al/hg.  they're cheap, easy to find, and they work well enough.  i've only had choking on occasion from when i ran an al/hg that was too large scale for the size of the condenser or if i had a ridiculously fast drip-rate where i should've slowed down some.  i've never smelled anything escape it before though, i'm sure vapor escapes but just not in a large enough amount to create a noticeable smell.  i toyed with the idea of a friedrichs but would probably want to give the friedrichs a test run by just heating the shit out of a flask of plain MeOH or H2O and see how it does with heavy reflux.  i hear they work wonderfully but don't know anyone who's used one for a vigorous reflux like the al/hg provides, so can't vouch for the idea of using one for this reaction.

Neil- As for drying the mgso4, oven treatment ensued.  400F for 2- 2.5 hours.  Went from clear crystalline rods, to white chalky powder.  High enough temp?

yep, you're good on the MgSO4
« Last Edit: December 27, 2011, 01:29:51 PM by NeilPatrickHarris »

thescientist3000

  • Pupae
  • **
  • Posts: 50
Re: Epoxidation using Performic. Buffered or Unbuffered?
« Reply #65 on: December 28, 2011, 01:45:07 AM »
There was a rat that consumed an estimated 40-75mg.  The rat felt little to anything, one could say almost placebo.  Is this in the threshold range?
Rats feelings:
1. dissolved very easily into water, and upon powder on tongue extremely sour/tart taste.
2. slightly sweaty palms, little underarm rat sweating.
3. light feeling in legs
4. auditory senses seemed entertaining, although without they do as much as well.
5. a little out of bodiness, or general slowness of sentences.
6. a little burping

When a rat talked to another rat, the more experienced rat said 200-300mg is likely tested for best effect, although other references state more of a 150mg range.

Thoughts?

lugh

  • Global Moderator
  • Foundress Queen
  • *****
  • Posts: 876
Re: Epoxidation using Performic. Buffered or Unbuffered?
« Reply #66 on: December 28, 2011, 02:09:52 AM »
Quote
When a rat talked to another rat, the more experienced rat said 200-300mg is likely tested for best effect, although other references state more of a 150mg range.

Thoughts?

Even for a new rat, that's a low dose  ::)  As has been said before, the rat's mileage may vary  ;)  It all depends on the rat  8)
Chemistry is our Covalent Bond

thescientist3000

  • Pupae
  • **
  • Posts: 50
Re: Epoxidation using Performic. Buffered or Unbuffered?
« Reply #67 on: December 28, 2011, 03:04:38 AM »
When Lugh said this statement the rat actually jumped up with joy, and excited for a new day of testing.  For a moment this little pesky annoying rat thought all the work was for failure, but perhaps the rat didnt eat enough that day.   :'( ;D

Damn rats.

lugh

  • Global Moderator
  • Foundress Queen
  • *****
  • Posts: 876
Re: Epoxidation using Performic. Buffered or Unbuffered?
« Reply #68 on: December 28, 2011, 03:30:02 AM »
It will take a few days to restore the various depleted compounds that are involved in mdma's pharmacology  ;)  Fierceness used to recommend piracetam and 5htp  :P  Dr Tom had a more complete formula that can be found using the search engines  8)
Chemistry is our Covalent Bond

thescientist3000

  • Pupae
  • **
  • Posts: 50
Re: Epoxidation using Performic. Buffered or Unbuffered?
« Reply #69 on: December 28, 2011, 04:28:56 AM »
I think the rat didnt take eough to deplete anything  ::)
5HTP is lying around for general well being, so 250mg and 50mg 5htp sounds good to go...for rats.

fresh1

  • conspirator
  • Dominant Queen
  • ****
  • Posts: 339
Re: Epoxidation using Performic. Buffered or Unbuffered?
« Reply #70 on: December 28, 2011, 03:02:30 PM »
Quote
Cold fingers are pretty damn solid. And get this, you can even make them via ghetto means for next to nothing, with soda bottles..... I'll elaborate if anyone gives a shit. A sort of bastardized DeWars.

I give a shit  :) I think I can guess 'how' to make one, but experience is god here ;)

I've never had, or used a coldfinger, but I can see their value, esp if they are "easy" to come by ;)

plus I'm curious as to what 'size' bottles/condensers used, and how they are put together ???

 But I'm a BIG fan of "unbreakables" ::

Seriously, all things which are effective cheap and ghetto are a plus in this day and age  8)
 
 Maybe as a separate topic, I guess in acquisitions maybe, I'm not exactly sure... :-\



"Curiosity is a gift"

Dr. Tox

  • In Stasis: See You In A Few Years!
  • Subordinate Wasp
  • ***
  • Posts: 145
Re: Epoxidation using Performic. Buffered or Unbuffered?
« Reply #71 on: December 28, 2011, 11:13:45 PM »
Well, frankly I'm not sure where it should go...

Cut the bottom off of a 2L soda bottle and the top off of a 1L soda bottle.

Place the bottom of the 1L inside the top side of the 2L and envision a cold finger arrangement...

Now, turn on an electric range/burner of your stove. Place the 2L cut edge on the element and slowly rotate until it begins to shrink. Shrink to fit your 1L finger....

Once a nice even fit has been achieved, use some high temp silicone sealant to create a seal between the two. Staple/sew them together at the seam, cover seam with electrical tape for general protection and let the sealant set up.

Poke a hole near the top of the 2L, near the seal point and affix a vapor exit tube of your choice and seal it.

Cut the neck/down side of the 2L to fit your reaction vessel or condenser joint. Seal, sit & wait.

Fill the 1L finger with acetone or alcohol & dry ice or whatever.

Use as required.
« Last Edit: December 29, 2011, 12:10:47 AM by Dr. Tox »
Alimentary, dear Watson; I had a gut feeling.

fresh1

  • conspirator
  • Dominant Queen
  • ****
  • Posts: 339
Re: Epoxidation using Performic. Buffered or Unbuffered?
« Reply #72 on: December 29, 2011, 12:58:40 PM »
thats pretty cool and very ghetto, I like

thanx for that
"Curiosity is a gift"

Sedit

  • Global Moderator
  • Foundress Queen
  • *****
  • Posts: 2,099
Re: Epoxidation using Performic. Buffered or Unbuffered?
« Reply #73 on: December 30, 2011, 05:16:46 AM »
Do you realize you just told people to fill a soda bottle with Acetone?
There once were some bees and you took all there stuff!
You pissed off the wasp now enough is enough!!!

Dr. Tox

  • In Stasis: See You In A Few Years!
  • Subordinate Wasp
  • ***
  • Posts: 145
Re: Epoxidation using Performic. Buffered or Unbuffered?
« Reply #74 on: December 30, 2011, 06:26:20 AM »
Do you realize that a soda bottle can hold acetone for some time?

I've never seen one get eaten through but then again, it was never a goal. If it were ideal, it wouldn't be "ghetto".

IPA & dry ice is fine also.
« Last Edit: December 30, 2011, 06:30:57 AM by Dr. Tox »
Alimentary, dear Watson; I had a gut feeling.

Sedit

  • Global Moderator
  • Foundress Queen
  • *****
  • Posts: 2,099
Re: Epoxidation using Performic. Buffered or Unbuffered?
« Reply #75 on: December 30, 2011, 06:32:38 AM »
I have used Soda bottle plastic dissolved in acetone(rather quickly i might add) to coat magnets to create a make shift Magnetic stir bar so sorry if I feel that this device would dissolve the second it was put into operation.
There once were some bees and you took all there stuff!
You pissed off the wasp now enough is enough!!!

Dr. Tox

  • In Stasis: See You In A Few Years!
  • Subordinate Wasp
  • ***
  • Posts: 145
Re: Epoxidation using Performic. Buffered or Unbuffered?
« Reply #76 on: December 30, 2011, 06:33:58 AM »
? Am I getting some sort of different plastic around here? Was my acetone shit? Maybe my memory?

Now I have to get more acetone and fuck with it or I can't sleep.
Alimentary, dear Watson; I had a gut feeling.

Sedit

  • Global Moderator
  • Foundress Queen
  • *****
  • Posts: 2,099
Re: Epoxidation using Performic. Buffered or Unbuffered?
« Reply #77 on: December 30, 2011, 06:36:49 AM »
I can't sleep myself so if you wish I will chop up a couple Soda bottles and dump some acetone in it and take a couple pictures. Give me an hour or so ok.
There once were some bees and you took all there stuff!
You pissed off the wasp now enough is enough!!!

Dr. Tox

  • In Stasis: See You In A Few Years!
  • Subordinate Wasp
  • ***
  • Posts: 145
Re: Epoxidation using Performic. Buffered or Unbuffered?
« Reply #78 on: December 30, 2011, 06:43:47 AM »
My sore eyes and myself thank you.

Go forth and destroy.  8)

Edit: I just called my dad and he said he's had it eat bottles. Another cat says he's got 2 & 3 L bottles that hold it just fine...

WTF is going on? An azeotropic issue, changing solvency or something? If it was alcohol in that ghetto rig and not tone, I'm going to kick myself in the ass.... somehow.
« Last Edit: December 30, 2011, 06:50:15 AM by Dr. Tox »
Alimentary, dear Watson; I had a gut feeling.

fresh1

  • conspirator
  • Dominant Queen
  • ****
  • Posts: 339
Re: Epoxidation using Performic. Buffered or Unbuffered?
« Reply #79 on: December 30, 2011, 06:59:24 AM »
Bahahahaha! classic! 8)

Quote
to coat magnets to create a make shift Magnetic stir

did it work?

Quote
WTF is going on?

Bulgarian plastic? :D
« Last Edit: December 30, 2011, 07:02:27 AM by fresh1 »
"Curiosity is a gift"