I Recently read a post concerning demethylation of catechols via snuggle, iodine and aluminum. In the post he used propane as an inert gas shield. He
dried it, and set it to burn from a tube at the end of the apparatus.
I am not concerned as much (though a little) about validity of the demethylation...as I am concerning Propane's viability as an inert gas shield. I
have considered its viability of recent. So this article's claim is hopeful.
Any advice is appreciated.
Also I have access to other nitrogen, helium, and argon. The allure of my local supermarket over the airgas shop.zed - 11-5-2015 at 17:29
Propane? Well it is contaminated by sulfur compounds, which accounts for its stink, but I suppose you could use it in some circumstances. I
personally would avoid it, on account of there are usually enough booby traps in the chem lab already. Some little mishap, the flame goes out, and
the lab fills with ever so detonate-able hydrocarbon gas.
The local super market (if you are in the U.S.) likely has an inexpensive supply of dry ice available. Use it to generate CO2. Not inert in every
circumstance, and replete with it's own hazards, but it is unlikely to blow your house off of its foundations.
....
drenchedingold - 11-5-2015 at 17:45
Thank you for your help. Boffis - 11-5-2015 at 18:31
I have used propane as an oxygen shield when preparing sodium cyanide from anhydrous sodium ferrocyanide and metallic sodium. The small amounts of
impurities in commercial propane fuel are not a problem. You just have to remember its not so inert in contact with air but if you are flushing a
reaction vessel you can always run the exhaust gas through a bunsen burner to burn it off.
methylation
drenchedingold - 11-5-2015 at 18:53
Via ctab/dcm or DCM/dmso pro***atechu****De.smaerd - 12-5-2015 at 04:43
I'm just going to reccomend you use Argon or nitrogen. Buy a 100$ cylinder and a cheapy regulator, you won't regret it. My main concern with propane
isn't it's sulfur based impurities, its the whole highly flammable gas thing.
CO2 is a great option if you don't use a lot of inert atmosphere but you know, things like grignards don't bode well with CO2 atmosphere.
[Edited on 12-5-2015 by smaerd]byko3y - 12-5-2015 at 05:11
I had propene and butene in my gas canister - that was a mad one. I was really surprised, I have no idea about why someone would fill the canister
with this gases. Btw, it was made in china.
Propane is a great inert gas, you could even use hexane, which is gaseous at 60°C+. Flamability is not a problem until you have a leak in your system
and forced to add more and more of the gas to the reaction vessel. The propane is safe at high concentrations. To e exact, propane is explosive at
2,1..9,5 % concentration, which is 10..48% based on air oxygen content. You will need a really fine mixture of propane-oxygen to make your glass
apparatus explode, and most likely the gas outside the apparatus will explode, but the fire won't enter the vessel.
OP, is this the procedure you want to follow? http://williestop.tripod.com/orgysynpages/4allylcatechol.htm...
[Edited on 12-5-2015 by byko3y]cmos6667 - 12-5-2015 at 06:00
I'm just going to reccomend you use Argon or nitrogen. Buy a 100$ cylinder and a cheapy regulator, you won't regret it. My main concern with propane
isn't it's sulfur based impurities, its the whole highly flammable gas thing.
CO2 is a great option if you don't use a lot of inert atmosphere but you know, things like grignards don't bode well with CO2 atmosphere.
[Edited on 12-5-2015 by smaerd]
this right here! don't just follow recipes you find on the internet,
otherwise you'll blow yourself up :/
may I recommend another experiment? the gaylord kraft lignin process:
sulfur, high concentration aqueous NaOH (pH 13 I think), heat above 100 C
followed by acidic workup to get the deprotected catechol
do this outside or in a fume hood because what comes out is dimethylsulfide... (it's how they used to make DMSO)
[Edited on 12-5-2015 by cmos6667]
[Edited on 12-5-2015 by cmos6667]Loptr - 12-5-2015 at 07:52
Methylation has nothing to do with DCM/DMSO with protocatechualdehyde. You named the wrong reaction.
If you methylate protocatechualdehyde you will end up with vanillin (4-Hydroxy-3-methoxybenzaldehyde).
Those reagents would be more fitting to a methylenation, which would give you piperonal (3,4-methylenedioxybenzaldehyde).
Seriously, just go with the nitrogen. It makes it one less thing that could possibly go wrong and result with you in the hospital.
[Edited on 12-5-2015 by Loptr]byko3y - 12-5-2015 at 08:34
Bout kraft lignin demethylation: the odor is horrible and there's a serious fire hazard in case... in case you use the original procedure, described
in the patent US 4250088. In fact you can use any thiol for the same purpose ( "Microwave-Assisted Cleavage of Aryl Methyl Ethers with Lithium
Thioethoxide (LiSEt)", "Practical demethylation of aryl methyl ethers using an odorless thiol reagent"). For some reason thiols love to cleave the
methyl bounds, they can even demethylate amines (via thiophenol).
[Edited on 12-5-2015 by byko3y]drenchedingold - 12-5-2015 at 08:53
I've ran the dcm /DMSO a few times. My research indicates gas shield is necessary to increase yields of piperonal.
I did mean the right reaction. My reference to the demethylation reaction was solely directed at the propane gas shield.
I already have a tank of nitrogen. I just fancy the propane use. I weld, have explicit knowledge and access. I just like low key.
Hope that helps sorry for being confusing. I am only wondering if propane can be used as an inert shield in a methylation reaction via either dmso
/DCM and the ctab method.
I obviously demethylated vanillin already. As I have the aldehyde annaandherdad - 12-5-2015 at 08:59
When I was in high school I used natural gas (available in the lab for the Bunsen burners) as an oxygen shield in the prep of phosphine. I would heat
pieces of white phosphorus in NaOH solution, after flushing out all the air with methane. When the phosphine started coming out in concentration, the
bubbles would ignite spontaneously and make the most amazing smoke rings that would float up quite a distance in the air. This was a demo I learned
from my father's chemistry books, which dated from the 1930's.
Yes, in those days, white phosphorous was available in high school chemistry labs. drenchedingold - 12-5-2015 at 09:02
Loptr you said :
"Methylation has nothing to do with DCM/DMSO with protocatechualdehyde"
Works well. Trying ctab. I have read a long discussion concerning its viability for methylation with success in the 40% range. Though 90 is possible.
I am sure the gas shield is necessary. I'll try with propane in a couple weeks and report
[Edited on 12-5-2015 by drenchedingold]
off topic kinda
drenchedingold - 12-5-2015 at 09:11
I called and asked sigma if ctab would be any problem to order or if it needed special. The tech didn't see any reason why " my roommate ordering this
with my card should be any problem. That it wasn't something I'd get in trouble for"...well just can't find any legal...
Anyone have experience ordering this. Is it watched. I am assuming not.
Its a lot cheaper local then not
[Edited on 12-5-2015 by drenchedingold]Loptr - 12-5-2015 at 09:34
Works well. Trying ctab. I have read a long discussion concerning its viability for methylation with success in the 40% range. Though 90 is possible.
I am sure the gas shield is necessary. I'll try with propane in a couple weeks and report
[Edited on 12-5-2015 by drenchedingold]
Where is methylation mentioned in the linked page you provided?
There is a difference between methylation and methylenation.
I called and asked sigma if ctab would be any problem to order or if it needed special. The tech didn't see any reason why " my roommate ordering this
with my card should be any problem. That it wasn't something I'd get in trouble for"...well just can't find any legal...
Anyone have experience ordering this. Is it watched. I am assuming not.
Its a lot cheaper local then not
[Edited on 12-5-2015 by drenchedingold]
CTAB can be bought elsewhere than Sigma, as it is used in the soap industry.
[Edited on 12-5-2015 by Loptr]drenchedingold - 12-5-2015 at 09:47
Ya I know. I just used their tech department to ask if its legal....and also thank you for the direct.
I'll just take it it is legal....soap industry
....
The company i found that i believe has the best price gave indirect answers to my question as well. Sigma gave the best response. She understood how I
had no idea that I was helping a friend and that I just wanted to make sure that it was legal to order like he said....sigmas specialist and I quote
"I don't see anything that should cause you any problem."
By the way thank you everyone for your feedback. I'll be more descriptive from now on so as to avoid so much confusion
[Edited on 12-5-2015 by drenchedingold]
[Edited on 12-5-2015 by drenchedingold]Loptr - 12-5-2015 at 09:50
loptr thank you. I will gladly return the favor....once I figure how to pm u drenchedingold - 12-5-2015 at 10:00
Thank you for the saving me timedrenchedingold - 12-5-2015 at 10:43
cmos6667 thanks for the direction. I made benzene and homemade nitric acid. Then nitrobenzene from the two. Then I reacted aluminum with bromine in a
soot trap. Lots n lots of fun and time.
By the way video procedures for the entire sequence were available via youtube the videos are all by chemical myst except the bromine and aliminum
reaction. There is one but the soot catch I made with construction paper. Like a chefs hat. Big tube with a top taped together.
Oh ya outside is a must. Unless you want to clean your hood for aluminum elemental bromine reactionFantasma4500 - 13-5-2015 at 04:27
i recall one member of SM did P4S10 using butane gas shield.. butane is rather heavy soo... it seemed to work out well
methylations is said to be possible to do with methyl nitrate, if you dare to handle it, that is..
if you really wanna go for it, then i recall it could be made by distilling nitric acid with methanol (less than 90% HNO3, even.. 70%?)smaerd - 13-5-2015 at 05:52
I see this thread in beginnings, I see advice about using highly flammable materials as inert gas shields when inert gasses are right near the users
local supermarket, nitrating methanol, and inquiry into whether a surfactant is legal or instantly recognized for illicit synthesis. I do think its a
cool idea to use propane or butane as a gas shield and burn off the excess in a burner, but I also see that being a serious problem for someone who
has never handled gasses before. Something seems out of place.drenchedingold - 13-5-2015 at 08:33
Your right Loptr. Methylenation. My apologies on the confusion.
As for my interest, who doesn't fancy using a two dollar bottle of propane and a torch head that's lying in the junk drawer. I do...and though its
insignificant to some, its not to others. I've always wondered and therefore I got a mbership on aboard that represents a lot of years of me getting
answers to my questions. I have no schooling in chemistry except through books..lots of books and these forums. Thank you and Hopefully I can put
back.
As for legality of ctab. I apologize if I stepped on a toe. I will not ask "is this legal" questions anymore. Thank you for being patient. First time
ever posting. I'm on it.
Thanks for the feedback guys
[Edited on 13-5-2015 by drenchedingold]drenchedingold - 13-5-2015 at 11:50
Propane does work...
From the torchbhead of a hand held propane torch
Attached hose, bubbled through flask of water,tube submerged 1".
Ran hose from that flask through damp rid
Ran hose to tire needle inserted on cork in three kneck's side kneck,
Propane exited flask via bent vacuum adaptor with glass cork in the female end. The male was put in female end of condensor during reflux. Vica-versa
for steam distillation . I ran a hose to a glass tube whose end vacated directly into a flame from a hobo alcohol stove. This was done under fume hood
with good exhaust.
Steam distillation yields look promising...I'll check back with weight....
Practice run DCM/DMSO methylenation on catechol as a substrate. Loptr - 13-5-2015 at 12:41
You might want to check this out in regards to the methylenation.
Attachment: ja00444a030.pdf (210kB) This file has been downloaded 803 times
[Edited on 13-5-2015 by Loptr]drenchedingold - 13-5-2015 at 16:10
Sorry brother couldn't open it. I'll try downloading a new pdfLoptr - 13-5-2015 at 16:23
The point of the paper was that the time requirement is lowered and yield is drastically increased with the usage of DMF with potassium fluoride, or
even better, cesium fluoride.
I also seem to recall reading an inert atmosphere isn't required for this particular procedure, but you want to ensure everything is very dry.
I have used propane as an oxygen shield when preparing sodium cyanide from anhydrous sodium ferrocyanide and metallic sodium. The small amounts of
impurities in commercial propane fuel are not a problem. You just have to remember its not so inert in contact with air but if you are flushing a
reaction vessel you can always run the exhaust gas through a bunsen burner to burn it off.
like to know more about using sodium ferrocyanide and metallic sodium to produce NaCN. thanksLoptr - 18-5-2015 at 17:04
If you really have to ask, the HCN vapor will likely kill you.
Not something to take lightly.
We had a member die a while back due to similar preparations.
The NaCN preparation on YT is actually of the member that died.skip - 21-5-2015 at 16:40
Ive already done it lots of times on a molar scale .I was wanting to know how elemental sodium is used in the process. I always used sodium hydroxide
. Have distilled hydrocyanic lots of times and never had a problem. Why does alot of people here always assume some one with a couple posts is dumb
as dirt.
[Edited on 22-5-2015 by skip]Crowfjord - 21-5-2015 at 18:53
The method of reducing ferrocyanide with sodium is posted on this forum. I think it is at or toward the end of the "Preparation of cyanides" thread,
under Chemistry in General. Search and you will find. skip - 22-5-2015 at 11:06
Sorry to hijack the thread. Thanks crowford I see now, I will stick to my way. Thanks again. Kind regards.
