PP in performic acid oxidation?

[raffike]

Raf was wondering if 30 liter PolyPropylene bucket could be used in performic acid oxidation.DCM doesn't readily dissolve PP afaik,dunno about isosafrole,but iso isn't in pure state in reacton but dissolved in DCM.Also whole mix is an emulsion cuz it's stirred hard during rx.Comments are welcome

[abolt]

Raff, If you are looking to upscale I suggest you check out Labtops Large reaction posts on the "buffered Performic". If you are not very careful you can end up with a dangerous exothermic reaction. I would not want to do that in a PP bucket.

[raffike]

Yeah,i've read em many times.He says to use SS but PP should work also.Rx temp can't rise over 40C(reflux) anyway and raf plans to use his 3 feet Aldrich super condenser in this dream.Labtop's writeup calls for 120 kgs which is bit too much for SwiRaf's friends.
Post hydrolysis ketone matrix will be distilled in small amounts(like 100 grams at the time,rest waits in the freezer) to prevent excessive polymerization

[RoundBottom]

i've said it before, i'll say it again.  pyrex carboys are the ticket.  anywhere from 9L up to 36L.  made of borosilicate.  heavy wallled.  fit a #12 stopper in the spout.  have a beer making supply place drill a hole 24mm wide (the 24 in 24/40).  then you can place a claissen in the stopper and affix all sorts of goodies like overhead stirring, addition funnels, and condensers.  if you find one that is aspirated, voila! 20L sep funnel.

performics of admirable size are simple... use standard glassware for the distillation.  multi-kilo size MeAm reactions, same as above.  fair sized Al/Hg Amalgams with foil and MeNO2 if you're still into that.

two ways i can think of to heat them, should you need it.  get a large institution size pot that will fit the carboy and fill it with hot water of the desired temperature.  alternatively, get a heating tape.  like a heating mantle, but in a flexable, sometimes rubber coated, long ribbon.  wrap it around the carboy as many times as possible, then connect to your mantle controller.

these ARE NOT, repeat, ARE NOT beer and wine making carboys.  same idea, different material.

[raffike]

Heating isn't needed.Vessel is only for performic acid oxidation.Even wine carboys can temp 40C with no problems.For isomerizing a la LaBTop,SS will be used.
230C and 3 hours.Reflux isn't needed AFAIK and 230 C will kick water out w/o problems.For 15% H₂SO₄ hydrolysis,SS reactor will be used.80 C and 3 hours as usual.Distillation of post-hydrolysis ketone matrix will be very time consuming,especially if pump is weak and brings ketone over at 140-150C - one must distill in small batches.

[abolt]

I have thought about a SS rig also Raff, but I figured that the H₂SO₄ Would mess with it or play with the reaction.

[raffike]

15%H₂SO₄ is pretty violent stuff,i guess it depends on what SS one uses.Some SS's are called acid proof or "inoxidable" or something,they make pool ladders out of em,maybe these could handle it.One also needs a thermostat which can keep mix around 80C,using variac is not recommended:it's difficult to stabilize temp with it.

[RoundBottom]

absolutely, yes!!!!  DO NOT use SS for the H2SO4.  SWIM tried that in a 10L SS pot, temp got a bit too high (like 90C-95C) and the whole reaction turned a dark copper green, and completely useless.  nothing recoverable.  and it wasn't a cheap SS pot, either.  SWIM has no experience with H2SO4 and PP or any other plastic.

[abolt]

I was diluting some H₂SO₄ on the kitchen sink when I accidently knocked over the bottle. The sink top had permanent discoloring as a result, even though it was washed down immediately.

Interestingly, Labtop talks of using SS equipment in his sooperdooper big Performics.

[raffike]

my bad...must find some big flask,he has a 12 liter one,but how he should attach rheostat?He can't just dump some probe into rx mix,can't he?

[raffike]

Interestingly, Labtop talks of using SS equipment in his sooperdooper big Performics.
Yeah,that made me wonder,i don't think LT is talking out of his ass,his atmospheric safrole isomerization worked like charm.

[abolt]

Raff, the temp. doesn't have to be exactly precise. Why not just stabilise a water bath at 85. C?

Or, use methanol to keep the temp. in check?

[raffike]

In raf's experience,80-85 C is best temp for hydrolysis.2 hours seem to leave some glycol unhydrolysed,3 hours seem to work just fine.Methanol is just like asking for trouble,if mix starts to reflux,one also needs to use a condenser which renders overhead stirring difficult.If using water bath,thermostat is still needed.Raf is sure there is some way to easily keep that temp stable.

[Rhodium]

Different stainless steels handle acids differently, they are not a single alloy. LT obviously refers to an acid-proof SS variety.

[Mr_Reflux]

Swim has a 2 litre PP container with overhead stirring and condensor attached. It sits in the top of a stainless steel water heater making a water jacket that can be heated to 104 -110 celcius (if salt water is inside) or can be flushed with cold water at will to bring it to 0 celsius. Very easy to control all temperatures in the below mentioned reactions with this system!!.  Swim has used it many times for:

Modified performic- dcm or chloroform
H2SO4 perfromic hydrolysis

Al/Hg amination with MeAm.HCL

to make MeAM.HCL via different methods involving Ammonia, HCL, Formalin, formic acid and temps 104+ celcius.

The PP is not affected in any way nor is the product.

[raffike]

This works like charm,no problems doing 0,5 kg reactions.Overhead stirring and external cooling as you can see.Inside the PP cooling jacket there is 7 liter 3-neck roundbottom.Stirrer is made out of power drill and variac.Works for hydrolysis also.

Performic reactor

400 grams of isosafrole being oxidised

Hydrolysis of glycol in 3 liter 3-neck(from 400 grams of isosafrole) with 2,4 liters of 15% acid

Same setup

[raffike]

If needed,raf will post more pictures.From that 400 grams of iso(iso was good,d20 1.120 and even bit more,safrole had a d20 of 1.095) he ended up with 245 grams of ketone,could have been higher but he has a lousy vacuum pump and some ketone scorched.Ketone seemed good,he aminated 60 grams at the time and constantly got 44-46 grams of amine hydrochloride out of every 60 grams of ketone(he did four runs).