Acid-Catalyzed Dehydration: 1,4-Dioxane

In this video, I make the cyclic diether 1,4-dioxane by dehydrating ethylene glycol and performing a few purification steps.

[@Erik-yw9kj]

Thanks for showing the cleanup - a lot of these sorts of videos usually don't show that (I guess it's not sexy or something) but I usually have a lot of questions about how to remove that kind of gunk, what to do with it, etc.

[@jhyland87]

9:30 holy crap... I had no idea bumping could be so violent.... Thanks for sharing! Thats the kinda stuff that ppl can learn from but usually gets edited out so the chemist looks better. So thanks for sharing it!

[@garrysekelli6776]

Bumping is like boiling. But chemists say bumping instead of boiling to sound smart. That's like my opinion man.

[@mattiasfagerlund]

The black sludge cometh - priceless!

[@Finnnicus]

Thanks for having so many videos recently, you satiate my hunger because I have no shed.

[@KallePihlajasaari]

Thank you for showing the cleaning excitement. We are often left wondering with you KZbin magicians always having clean glass for new experiments, there is always that small doubt that you just chuck the dirty stuff out when it looks hard to clean.

[@fieroboom]

OMG I finally saw you mess something up! 😂🤣 I was actually thinking "I wonder why he's not using a lab jack this time..." 🤔

[@bjthinks]

Hooray, another volcano! Thanks for detailing the post-gunk purification steps.

[@Arnthorg]

12:00 very refreshing to see glassware cleaning in a chemistry video

[@UC235]

Dioxane is miscible with water and forms an azeotrope. Salting out water with NaOH or KOH is about the only effective way to dry it. You should have removed and discarded the tarry lower layer instead of adding it to the flask. This reaction produces another product as well: 2-methyl-1,3-dioxolane (possibly 20-30% of the yield). That is, the ethylene glycol acetal of acetaldehyde, which forms through acid catalyzed rearrangement of the glycol. This boils at 82C and without a very efficient fractionating column is a pain to remove. It will withstand treatment with sodium (which melts, forming shiny metallic globules in refluxing dioxane). However, at the slightest hint of strong acid and water, it comes apart to EG and acetaldehyde and rapidly discolors.

[@DougsLab]

+UC235 Ooo, good point. I know about the pinacol rearrangement but I had always assumed that since there is a tertiary carbocation intermediate that it would be nothing to worry about with a vincinal primary diol like EG. I think I might be able to fraction it out to see how much is there. I have a 400mm Hempel column with raschig rings, and the BPs are about 19 degrees apart...

[@chemiosmoticphosphorylatio3198]

+UC235 Why did you stop making videos UC235?

[@ScienceWithJames]

Chemiosmotic Phosphorylation I've seen him on science madness lately, so he must be busy/lost interest in making videos.

[@alphatks]

It Think He Made Mistake On Drying! You Should Have Used Base As UC Said! & The Byproduct Dioxalane Won't Be A Problem, Only Thing Is to Find A Way to Separate It! Ethylene Oxide, Dioxane, Dioxalane, Diethylene Glycol, Triethylene Glycol.

[@firstmkb]

I *really* like the way you showed the mishaps, and even more how you managed to recover from them. Things don't always go smoothly when making anything, and being able to recover is important. BTW, I think I made that black product in my kitchen, but acetone wouldn't touch it.

[@vector8310]

Fantastic opening minutes, in terms of clarity and conciseness.

[@gogear131]

Yet another good video Doug. Keep up the great work.

[@soroka6983]

Hello, for the fist distillation start slowly raising temperature, throw away anything that coming over before 49 degrees Celsius. Only keep the distillate from 50 degrees Celsius to 103 degrees Celsius. Or you going to get a lot of different byproduct that is hard to separate later.

[@dimaminiailo3723]

What byproducts are you talking about? I always thought that all tar etc. forms during the dehydration process and fractional distillation of the reaction mass is a waste of time

[@garrysekelli6776]

A man and his column are inseparable.

[@brucefrye8799]

I really enjoyed this presentation thanks

[@arulexport2701]

Hi sir your growing my chemistry knowledge Thanks a lot

[@malcolmhein1858]

Great video. Informative and educational. Along with NurdRage's video, I was able to make dioxane on first try withourt messing up. But, Doug, my man, you talk way too fast and should fine tune your presentation, polish it up. Still, I rank it right up there witrh NurdRage. And that is a compliment.

[@sciencoking]

"You can't screw it up" 10 minutes later..

[@benearhart1224]

You turn off heat but NOT the stirring. In fact, in this case, you should turn the stirring up faster if possible.

[@oak_meadow9533]

Really want to see you. So interesting.

[@benearhart1224]

I've found K2C03 to be an excellent entrainer. MgS04 seems to be the choice of the u-tubers but pot-carb was what I came up with after reading a few papers. I have a 3 distillation process for ethanol. Kind of overkill but I think I'm getting proud of it. A good 5ml shot of it is an ... experience.

[@jacobkudrowich]

Distilling ethanol 3 times is unneeded

[@benearhart1224]

@@jacobkudrowich Well .... it depends. I don't have enough vacuum. So I do once with a column to get to 95% then once with the k2c03 then optionally, I'll distill it one more time after using sieves just to get the material out. Which step you would eliminate? I get 60% and it isn't hard to run it through once just to save the amount of entrainer when going from 95% to nearly absolute. That is pretty damn dry but , by my taste, it gets drier after sieves. I can tell the difference by taste. It's not so much taste but more how intense the burn is before it settles into tasting like alcohol. Sometimes I just use it off of the sieves but the ones I have shed a bit. I have two foot columns: Snyder-esque Vigreux, Graham (coiled), and Allihn.

[@benearhart1224]

@@jacobkudrowich I think without vacuum you can do it in two distillations. BTW, I found this really good paper on solvent drying. It's a "JOC Article" entitled "Drying of Organic Solvents: Quantitative Evaluation of the Efficiency of Several Desiccants". Some real interesting findings in there.

[@Savage1872All]

I have fredrichs condenser and I was wondering: which condenser when and why? Can I use fredriches condenser for all needs? Thanks

[@SodiumInteresting]

Doug, what do you mean by store over base/na metal? you mean put a nugget of sodium in the bottle with it?

[@davegeorge7094]

Cut out a hole in your table where the mantles are, use shelf slotted hanger for adj. plywood table. Or use threaded rod floor stand underneath hole in the table. Or quick clamp stand to vert. riser. Nice to have work at comfortable level.

[@chaoticchem]

Did you not notice that this video is over 5 years old and Doug no longer does KZbin videos? There's about a 99.999% chance that he will not see your advice, though it is great advice.

[@NicolasBana]

Yay ! Very very nice video, i'm following organic chemistry classes and i find your videos very entertaining :D I've dealt with organometallics before and it's really no joke n_n I have a question : Did you bought all of your apparatus ? Or did you have some contacts that can give you some / sell it to you for a lower price ? I'd like to build myself a little lab and your videos are great for that :D

[@SodiumInteresting]

Ali express is good for glassware if you've not discovered this. Very cheap and quality is good. Amazing considering the skilled workers needed to make them

[@refluxcatalyst7190]

It's fully saturated, not unsaturated.

[@RavenFly1232]

I feel for you, having to clean your columns and trying to save the products. Happened to me a couple of times XD But awesome video anyways! :D

[@LaserJake99]

You should add sulfuric acid to the azeotrope to destroy the 2 methyl-1,3 dioxolane. This will hydrolyze it back into ethylene glycol and acetyladehyde which can be removed by the hydroxide polymerization and a redistilation. There is a lot of 2-me1,3 dioxolane that comes over with the azeotrope at 85-90C

[@PauloConstantino167]

Doug I love your videos. I wonder if you could do a video where you go over some of the finer points about your lab? Thank you.

[@venkateshkademane2098]

SUPERB LY DESCRIBING VIDEO COULD I GET PROCESS DETAILS FOR PRODUCING DI BUTYL ETHER

[@joshuapeters4384]

can I use sodium sulfate or magnesium sulfate to dry it?

[@williamjemeyson5101]

21:05 turn on captions

[@chaoticchem]

??? I can tell what he says just fine. What part are you not understanding?

[@jamest.5001]

I came across this channel. while looking in to how ether is made. and I'm looking in to home made fuels. like from distillation of wood. I want to run my generator at my off grid home.. methanol with about 10% ethanol. with very little h2o. could you tell me if this will be practical ? or could I run to strait from the still?

[@Mikeb0224]

What is the black power supply that you have plugged into the back of your hood for your mantle called? And where can I buy one?

[@SoCCeRBaLL1996]

At 15:10 and onward, in the separatory funnel, is there not a layer on top of the 1,4-dioxane? And if so, why was that not separated out?

[@plutoniumiscool]

You should make a video on the extraction and purification of 1,3,5 trioxane from solid fuel tablets.

[@UC235]

+plutoniumiscool Crush the tablets/bars (make sure you don't have ones containing hexamine as well), and distill with a short air condenser. Dye and waxy crap stays in the distillation flask and clean 1,3,5-trioxane passes over at 115C. It freezes at 62C so avoid any narrow spaces that might quickly become plugged by solid.

[@zacharysinger5370]

Short Path distillation may be better?

[@gogear131]

makes me wish i was good at chemistry. i was very interested in it at a time but the math that is required killed it for me

[@pelegsap]

I actually cringed when the goo came up... reminded me of something that happened to me once in org synth lab back in UG ;) btw - how come your Keck clips are orange, if you have 24/40 glass ground joints - aren't the 24-size Keck clips suppose to be green?

[@SuperKillerkarnickel]

What about using it to make glacial acetic acid - it forms an azeotrope with water that boils below acetic acid ? Just a crazy idea ;)

[@SoulDelSol]

You're putting sodium in end bottles for storage?

[@tyt0uoff146]

Yes

[@chaoticchem]

Yes, it destroys the explosive peroxides that form when the dioxane touches air. You don't want those peroxides to form at all.

[@upaiaq]

Can you store with copper wire to keep the peroxides down?

[@tyt0uoff146]

Not sure ... Better be using KOH or NaOH

[@chaoticchem]

No, you cannot. Do as the man says.

[@jaudry123]

Estimated Doug, can you kindly help me to get treethylene glycol, either how to syntetize it or where to buy it, thanks before hand J. Audry

[@michaelremsnyder3483]

I have a question what kind of reaction would form if u mix vineger and 1 4-dioxane?just asking because it has a sweet smell

[@charlesmcnew1051]

Doug and 42 Doug should do collaborative KZbin video. Sweet.

[@flaplaya]

What would be the product using 1,4 butanediol instead?

[@94franz]

hi. just one thing i don;t get @0.36 "Oxygene has a lone pair of electrons". what do you mean by that? afaik O has 2 valence e- (2px,y) which are used with the 2 C and remains only a full 2pz. so what do you mean by lone? maybe it's just a matter of interpretation from my side. And as always "thanks for producing such videos" ;) EDIT think i got it, it related to Dative Bond right? i find it ambiguous to call 2e- in a full orbital a lone pair, as they are not so alone... comment?

[@jogandsp]

That's just the convention in English. A non-bonding pair is also known as a lone pair.

[@Barnekkid]

Wow, that was interesting.

[@Retrogamer71]

Where does your sink drain go?

[@karatepro97]

so, what exactly do we need that column for? Can't we just distill it without it? btw, nice video ;)

[@thereptileguyz7265]

The funniest thing about this experiment or demonstration is in the beginning you said you can't mess it up sounds like a jinx you can always prove yourself wrong it made the video more exciting at least

[@chaoticchem]

Lol, he meant the synthesis, which was not messed up. He just made a mess is all. 😉

[@chemotrail7160]

isin't ethylene glycol a vicinal diol?,so the acid didin't cause a Pinacol rearrangement to produce Acetaldehyde

[@AuraRisen]

Wouldn't it be better to keep stirring? When that happens to me, I just stir a lot, the foam doesn't rise!

[@Angrychemist666]

Dean stark apparatus would take care of removing H2O from the dioxane!!

[@jadghalayini1446]

Would this work with sodium carbonate? Seems easier to get.

[@benearhart1224]

Potassium carries a larger hydration shell than sodium.

[@jklbyrdman]

What if I have a mixture of ethylene glycol and diethylene glycol. They come as chafer burners. Would the reaction not change were no sulfuric acid would be needed. But maybe another acid to still keep the reaction on the right path?

[@chaoticchem]

Other acids have too low of boiling points and if you tried using another acid it would come over with the dioxane. That's why sulfuric is needed.

[@wgm-en2gx]

As a layman, I'm completely fascinated by chemistry. Could someone enlighten me on the issue of "bumping"? What is it and how does the stir bar prevent it?

[@bjthinks]

+wgm4321 In this context, bumping means irregular boiling. It happens if you boil a liquid in a very clean container. If there aren't any nucleation sites where a new vapor bubble could form, the liquid will superheat slightly, then a large bubble of vapor will suddenly and forcefully appear, jarring the apparatus and splashing the liquid. If you add a few inert pebbles, often called "boiling chips", they provide enough nucleation sites that boiling is smooth and continuous. A stir bar can often serve the same purpose.

[@wgm-en2gx]

+Brian Johnson Thank you for the excellent explanation. I've watched a number of videos on the instant ice/exploding water phenomenons and nucleation so your explanation made perfect sense.

[@doubtingthomas1312]

💜💜💜

[@SoundOfWaveform]

How dose 1,4-Dioxane's chemical properties compare to 1,4-Dioxin, Is it as different as benzene compared to cyclohexane? I know hydrogen saturation can make a big difference in chemical properties.

[@ThePaintballgun]

If your dioxane and water both come off together you haven't really driven the reaction to completion have you? I guess the lack of acid in the receiving flask would limit the rate of hydrolysis, but surely there's a way to reduce the effective water concentration.

[@NextGenAge]

Any updates?

[@raa6504]

' you can't screw it up' Wanna bet? I managed to screw it up. I believe my acid was too dilute, about 70% after measuring density.. i redistilled it but still, adding naoh made everything a goopy tarry mess with polymerased stuff at the bottom and black liquid which i believe it's water and tarr... I have to check my thermometer too, I don't think it's calibrated..

[@AlexBesogonov]

Can you purify it by crystallization instead of distillation?

[@tyt0uoff146]

You Can try with 1-4 dioxane but this procedure Works well with benzene

[@chaoticchem]

It's a liquid, not a solid....

[@thecrudelab3204]

Why do you need to use sulphuric acid? Can't you use hydrochloric acid or other types of acis?

[@David-fh6rr]

I think, HCl might just distill off, but generally speking, H2SO4 is the acid of choice for reactions like this because of its high boiling point and because it's not nucleophilic. If HCl reacts, it might yield nasty chlorinated byproducts.

[@lorenzolafayettequadri5275]

Rub acetone-wet paper towels against your reaction flask to cool it down faster

[@chaoticchem]

Lmao! Yeah, if you want it to catch fire in your hand. If anyone else reads this comment, do NOT do this. Acetone is highly flammable and running a reaction flask with a paper towel that is wet with it while the flask sits in a heating mantel that is ON will cause it to catch fire if it touches the heat coils or the netting that is very hot. This guy is trying to get someone hurt.

[@xelionizer]

WHERE IS THE LINK???

[@alllove1754]

Hehe, but I feel your pain there, but love the narration

[@AvZNaV]

"Dude's Red Hot Devil Potash"

[@davidlambaugh6856]

"Ohhhhh, dear......"

[@pietrotettamanti7239]

15:39 you should have poured it from the top

[@benearhart1224]

Oh yea, one last thing, stabilize with BHT and 3A sieves.

[@benearhart1224]

man, you turn the stirring UP to stop foaming lol.

[@alockworkorange7296]

As some1 whos literally making dioxane right now that is not true

[@benearhart1224]

@@alockworkorange7296 It depends on the situation I suppose. Turning up the stirring increases the heat draw from the source and thus the boiling and so it can increase foaming. However, if the problem is that your foam is too persistent, then turning up the stirring will break it down by sucking it back into the liquid. In general, when faced with foaming, the first thing I try is lowering the heat and raising the stirring way up.

[@benearhart1224]

@@alockworkorange7296 FYI, having done this reaction a couple of times now, I'd say you need to distill the dioxane a second time if you want something that is actually relatively free of water and MEG.

[@benearhart1224]

@@alockworkorange7296 Also, if you're using drain cleaner, you will likely get a lot of SO3. It's very reminiscent of HCl in terms of smell but does not destroy all the metal in the house nearly as fast. (An open bowl of ammonia nearby helps to fix acid anhydrides out of the air. ) Refluxing or even just simmering in an open flask will get rid of that.

[@chaoticchem]

@@benearhart1224 dude, no need to keep going on about it. That guy proved you wrong. You were talking specifically about dioxane, not in general. Stop trying to save face. 😂😂😂

[@zbeekerm]

shoulda used a lab jack... lol thanks for the awesome videos. Lol, you just said use the lab jack after I wrote that

[@benearhart1224]

what you can do is use Allihn column with either no cooling or just slow air flow from a fish pump. Also, the biggest thing is to insulate your junction with tin foil. That will eliminate excessive reflux.

[@benearhart1224]

In fact, I rarely use water cooling. I have a two head fish air pump. One goes to the column and one to the condenser.

[@oak_meadow9533]

No lab jack!

[@leminh9669]

2HO-CH2-CH2-OH->C4H4O2(benzene cycle with oxi is on the top and the bottom )+2H2O

[@Calabi]

look like Venom coming out

[@Mehtzful]

11:25 you get a small tutorial on how to clean a bong. Drugs are bad kids

[@garrysekelli6776]

Old school yt videos.

[@alanchang9133]

Could you please tell me your Facebook I am a chemistry lover and I have a home lab ,I want to talk to you on Facebook!

[@skidderjohn]

+常清扬 i love science to would you like to be friends on fb