Making Diisopropyl Ether
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- Опубліковано 22 сер 2024
- Welcome to Episode 12 of Molecular Playground! In this video, I make diisopropyl ether! This bulky ether is a better solvent than diethyl ether because of its extra methyl groups. It can dissolve other bulky alcohols, ketones, aromatic compounds, and alkaloids.
Warning:
May form explosives peroxides when standing in air or exposed to light. Handle with caution!
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please check the audio track for your video. it is entirely mono, which would be fine, but its mono on one side.
if you cant hear it (or want to watch this video with audio on more than one ear)
Windows 10 search -> Turn mono audio on or off
also yes worthy of note, peroxides...
im not sure if sodium metabisulfite is good to reduce the peroxide formation? i mean peroxides still form, and the only way they are being removed is by coming in contact with the salt. which is, rather unlikely in an unstirred stored bottle. id use something more dissolvable, something like 2,4,6 tri tert butyl phenol.
I like this isopropanol chemistry. It's also cool to use it in a Fischer Esterification with acetic acid to make isopropyl acetate. Using acetic acid in excess instead of the isopropanol makes purification easier because you can just neutralize with bicarb. Easier than fractional distilling to separate from the alcohol if you use that in excess instead.
You should include a note about potential side products. Also it is good practice to redistill, particularly for this synthesis.
What about the risk of peroxides?
@@MolecularPlaygroundthey Can Be unstable
@@MolecularPlayground treat with sodium metabisulfite. distill over ferrous sulfate using a high bp chaser solvent.
@@MolecularPlayground they don't really form in a matter of several minutes. still, don't distil to dryness
@@MolecularPlayground
You can also use MnO2, it decomposes organic peroxides too.
But Fe(II) SO4 works just as well.
Great video.👍 Tell me, please, can you show the synthesis of Valeryl chloride?
It’s easy on paper but difficult in practice. I would have to get some amyl acetate (most common commercial form of pentanol), hydrolyze it, isolate the alcohol, oxidize it to pentanoic or valeric acid, and react it with thionyl chloride or phosphorus pentachloride-both of which are painful to make. I definitely do have plans on making it in the future though!
I always like videos that show alternative, and sometimes easier syntheses.
Sometimes a bit of yield or time is a good exchange for a more direct but escessive toxic route in my book!
Will you do some project where you use this ether?
Later when I extract natural compounds from plants
@@MolecularPlayground
You can try re-doing this experiment with Phosphoric Acid and a Dean Stark apparatus to reduce the oxidation caused by Sulfuric Acid.
To reduce the conversion to propylene, an additional Lewis Acid catalyst like Chromium (III) phosphate can be used to stabilise the alcohol by briefly forming intermediary esters which convert to ethers.
This is cool mate, you're giving pretty good explanations, not a SUPER sketchy chemical, good job.
“I explain how to make it not explode at the end”
God…..I REALLY hope everyone watched till the end…
really cool vid, appreciate ur work, keep going!
I was interested in making i-Pr2O, and managed to find a single description of its synthesis, which consists of distillation of equal volumes of 58% H2SO4 and i-PrOH, giving 40% yield. Seems like nobody wants to handle this compound. Btw thanks for the perfect cut at 4:44
40% yield? Yikes! I wanted to make an actual viable route to diisopropyl ether that gives yields comparable to diethyl ether. I probably could have gotten 70% if I gave it another 20 hours. Anyways, I do plan on making another video where I test which is a better solvent: diethyl ether vs diisopropyl ether
@@MolecularPlaygroundThese 30% of yield don't make up for the utter slowness of the whole process, 100 hours for 500 ml of i-Pr2O is a pure insanity. Additionally, it seems possible to recover the excess of i-PrOH from the distillate, and this fact renders the low-yield process rather attractive. I like long-time syntheses, but they usually don't require being babysat. If you want to develop a viable procedure, I would recommend it be no longer than 8 h in total, preferably 4 to 6, even if it means sacrificing the conversion of i-PrOH (not to be confused with yield). Use a Vigreux column for separation of alcohol and ether. i-Pr2O and Et2O should have similar dissolving properties.
“Pure insanity”-I love it! It only took though 70 hours, and I wanted to convert a whole bottle-950mL-of alcohol into ether. Of course it would be much shorter if I just stuck with 250mL I first used.
@@MolecularPlayground I said it's possible to convert the whole bottle in several hours rather than several days if you slightly change the method you use. However, I like mad chemistry, and this particular video was interesting to watch
Thanks! You are right that it maybe could have taken a few hours, but I was scared of using higher temperatures because-and I’m not sure if you have seen my community post-but higher temps caused that garlic liquid to be distilled. Behind the scenes: I lost two and a half days hoping that was some transient thing but it just kept getting stinkier the more heat I added.
Nice experiment, i think you could distill your ether over KMnO4 to remove traces of IPA (to acetone b.p= 56°C) but that's just fancy chemistry JAJA well done new subscriber 👍
wouldn't that make a lot of peroxides
Have you measured it's boiling point? I would imagine some isopropyl propyl ether impurity could increase it easily over 70C.
It never even reaches 70 though. Most it has gone up to is 58C during distillation. It does boil at 70C in a separate test, but the proof is the density which is shown.
how about just adding dry iProOh to cold concentrated sulphuric acid, that leaving group would promote more ether production rather than propene because of the cold
There does need to be some heat to promote the condensation of two alcohol molecules. A cold solution of acid does not spontaneously make ether.
Msde this before, its a good extraction solvent for O chem but it tends to form peroxides,
Very informative video's brother ❤
Question for you; if the IPA boils at 82*C, while the IPA ether boils at 69*C, wouldn't it be better to set the reaction temp to 70*C? wouldn't you have a bunch of IPA in the ether produced at 170*C?
It’s kinda hard to explain. Basically since ether boils at 69C, the atmosphere in the reaction flask is 69C no matter the temperature of the solution. This is because ether’s transition from liquid to gas depresses the atmospheric temperature. So even when I add the alcohol, because of the ether, the alcohol will not instantly boil off even though the solution is 170-190C. But take my explanation with a grain of salt. I do not know the exact thermochemistry and physics behind why ether is solely made.
@@MolecularPlayground Hem... I would be curious to see if there is any free IPA in the product. If you have any acetic anhydride and pyridine, you could run a hydroxyl value test on it (message me if you want details, but its a standard ASTM method)...or an IR would also work but less accessible for the home chemist.
Hello guys can i ask you something, my itric acid is white fuming but when i weight it, it's just 121 gram per 100ml nitric acid that mean my concentratio of nitric acid is just bellow 40% but why my nitric acid is white fuming? Anybody have explanation, thank you.
Pretty much any volatile strong acid going to fume a bit at enough concentration. White fuming nitric acid is above 97% and has had the free nitrogen dioxide removed from it hence why it's colorless instead of red. Yours isn't considered as WFNA but just plain concentrated nitric acid which still fumes.
Can it be used instead of ether in Grignard?
I believe so. It might not complex to magnesium as strong as diethyl ether or THF, but it is extremely impervious to water so that will never be a problem.
Thats not the way to measure density of liquids . Taking a 100ml measuring cylinder will never give you accurate results. You should have used a small volumetric flask or a relative density bottle or a pyknometer .
I wouldn’t say “never accurate” results but not “EXTREMELY accurate” results. However, using a 100mL to get density is accurate enough to know whether you made product or you messed up big time. They (glass manufacturers) would not make 100mL cylinders if they were not accurate. I’m surprised you didn’t blame the scale-which I would-because just 0.1 difference could drastically change density and estimated purity, and that could happen because an extra weight of 0.06 or even 0.05 could round the whole tenths place up.
Cool
I think you need to do a better job of purification/characterization. How do we know the product isnt 50% starting isopropanol?
Because the density isn’t 0.786 or anywhere close to it. Impurities would skew the density, you know. Also, the thermometer (unseen) never even reaches 70C (10 degrees under alcohol boiling point)
@MolecularPlayground Okay brother, just offering constructive criticism. Otherwise good, I would like to try something similar at some point, diethyl ether is pretty sketchy to work with.
@@MolecularPlayground
There’s still a good chance you have 10% iPrOH in that ether (depending on the accuracy of your measurement), if only by the simple virtue of ether vapours carrying the alcohol vapours with them.
To reduce the possibility of contamination, a fractionating column should’ve been used.
@@cezarcatalin1406 What would the density look like with 10% alcohol?
Does it smell like ethyl ether?
It has a more pronounced sharp minty smell
A bit stronger smell that isn't as sweet.