The Fischer Esterification: Methyl Salicylate

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Doug's Lab

Doug's Lab

Күн бұрын

Пікірлер: 163
@One2rock
@One2rock 8 жыл бұрын
seriously, your vids just keep getting better.
@DaffyDaffyDaffy33322
@DaffyDaffyDaffy33322 8 жыл бұрын
Ending a several month hiatus with two back to back long videos? Today is a good day
@jhyland87
@jhyland87 3 жыл бұрын
Then he disappears again :-( Very sad - Definitely one of the best chem ToobYoubers.
@johnblacksuperchemist2556
@johnblacksuperchemist2556 3 жыл бұрын
GREAT VIDEO.......I love how he goes over the things in the pot after a reaction and his process of thinking of how to extract and purify
@r3pub1ic_03
@r3pub1ic_03 5 ай бұрын
You and your experiment are great! Your mind is very clear, and yield of experiment is very high!
@mikeg4972
@mikeg4972 3 жыл бұрын
11:08 Lab Jack: " Hey,I need some oil here!"
@tek4
@tek4 7 жыл бұрын
I miss the videos and love the way you teach. I hope all is well Doug.
@edgeeffect
@edgeeffect 4 жыл бұрын
There's much worse things a chem lab can smell of. Miss you Doug.
@THEGREATONE420
@THEGREATONE420 8 жыл бұрын
Doug is always on point. Great insight into your tnought process when dealing with roadblocks like emulsions.
@BillAnt
@BillAnt Жыл бұрын
The toad would have made a better stir bar. No electricity needed, just let it kick around in the mixture. And once distilled, it would have made a nice meal too with winter-mint seasoning. lol (jk)
@msp423
@msp423 8 жыл бұрын
Just finished Orgo and fell in love with the labs! Thank you very much Doug for providing an outlet to enjoy this science for those that don't have access to a proper lab set up
@lukejefferson2982
@lukejefferson2982 2 жыл бұрын
Can U use acetone instead of ethonol
@chemiosmoticphosphorylatio3198
@chemiosmoticphosphorylatio3198 8 жыл бұрын
Hey, why did you stop making videos? Are you okay dude?
@libalj
@libalj 8 жыл бұрын
You're not dead or in jail, YAY!
@ArgonZavious
@ArgonZavious 7 жыл бұрын
11 months now, get worried
@williamackerson_chemist
@williamackerson_chemist 7 жыл бұрын
I just would have expected him to leave a message or something if he wanted to stop uploading to the channel... It seems like he just disappeared.
@s_sedimentality
@s_sedimentality 4 жыл бұрын
yea he is completely gone now
@CrusaderGundam
@CrusaderGundam 8 жыл бұрын
I have a Organic chemistry exam shortly and this is one of the rxns i have to study! Nice
@douro20
@douro20 2 жыл бұрын
There are actually Teflon Keck(R) clips. We have toads all over the place here but I have never seen them in our basement.
@jhyland87
@jhyland87 3 жыл бұрын
10:54 you said the color _didn't_ change? didnt it go from purple to yellow? or am i seeing things?
@ohwell7504
@ohwell7504 8 жыл бұрын
What happened to him?
@kieranodea771
@kieranodea771 6 жыл бұрын
As said in the vid, wash glass ware after pouring acids. I picked up a glass with good old thick sulfuric acid on it and didn't know it. Soon my hand itched and then burned real bad and I realized I messed up for lacking to ware gloves.
@aussieausbourne1
@aussieausbourne1 2 жыл бұрын
I know this video is old I just had to mention that if you have any alcohol candles you use for any of the experiments that you do you could use the winter green contaminated methanol and get a nice smell at the same time
@KingNast
@KingNast 8 жыл бұрын
That was a good one! I like the more in-depth videos even though I barely understand the chemistry.
@chrishing8491
@chrishing8491 8 жыл бұрын
such a great video , specially liked when you showed what you where doing on the whiteboard then showed the practical side just made a beginner like myself understand what's going on a bit easier , keep up the great work with the awesome videos
@BillAnt
@BillAnt Жыл бұрын
I agree, learning the theory before the reaction is more educational than just mixing a bunch of chemicals.
@petkotzvetkov6528
@petkotzvetkov6528 8 жыл бұрын
Thank you for your great chanel! I value the most the lecture in the begining of every preparation...
@Fummy007
@Fummy007 8 жыл бұрын
That was fun to watch. I don't know about this Winter Green smell, its not common in the UK, so im going to try and find some wintergreen sweets so I can get what you were talking about.
@MostFolkCallMeOrangeJoe
@MostFolkCallMeOrangeJoe 8 жыл бұрын
I'm in the UK too, and I've never even heard of wintergreen.
@googleeatsdicks
@googleeatsdicks 8 жыл бұрын
Do you know listerine mouthwash? It contains methyl salicylate.
@MostFolkCallMeOrangeJoe
@MostFolkCallMeOrangeJoe 8 жыл бұрын
Anticonny So it's a 'chemically', minty scent?
@krisztianszirtes5414
@krisztianszirtes5414 8 жыл бұрын
I have days old recorded footage for this for my channel. Guess I will wait a bit now ._. Also, I had the exact same purple colour in the start, still haven't got to reflux it though. Can it be due to iron contamination from my starting materials? And for the last note, can I use for example ethyl acetate as the solvent in the organic extraction? The distillation later on would be pretty efficient and easy on power use (if you care about those at all here)
@agent475816
@agent475816 8 жыл бұрын
"Ok, back to non-frog related activities." lol
@jonhoyles714
@jonhoyles714 8 жыл бұрын
good to see u back doug great vids
@Amena.Amer.Official
@Amena.Amer.Official 3 жыл бұрын
what are the key findings, significance and major conclusions of this process, I didn't get it
@mikebarnacle1469
@mikebarnacle1469 7 жыл бұрын
Doug please come back and make more videos.
@establisha
@establisha 2 жыл бұрын
please do some more videos, ur truly missed!
@RobertSzasz
@RobertSzasz 8 жыл бұрын
Did you try just warming the solution back up to keep the salts from precipitating out?
@johnblacksuperchemist2556
@johnblacksuperchemist2556 3 жыл бұрын
QUESTION............Why doesn't the hydroxy group on one salicylic acid molecule react with a carboxy group on another salicylic acid molecule and form an ester???????? Is it just steric interference??????? Or it does happen but since there is so much excess methanol that is not sterically hindered that it only happens to make trace amounts?????????? I just watched the video again and you answered my question at the end with font saying that last high boiling stuff left in the flask was probably salicylyl salicylate
@henryrenyz7232
@henryrenyz7232 5 жыл бұрын
When I perform this reaction I measured the temp and found it much higher than 64C(b.p. of methanol), which is about 104C, because of the protonation of methanol by conc.sulfuric acid, just like when you make ether at 130C using ethanol which is above its b.p.
@goodsir2551
@goodsir2551 8 жыл бұрын
It's been 3 months now, where are you dude???
@rabinator33
@rabinator33 8 жыл бұрын
Nice video, especially the frog! Really glad you are back. One suggestion, maybe instead of/ in addition to some of you updates where the reaction has to sit for hours at a time, you could time lapse some of the boiling or distillation. Think it might make for a cool shot. Anyways, keep up the great work!
@InDmand
@InDmand 8 жыл бұрын
Gotta give you a thumbs up for the detail you put in to these videos, they bring back memories of my organic chem prac classes. I even had to stop the vid at the start to draw out the reaction mechanism here xD
@agent475816
@agent475816 8 жыл бұрын
Why would toluene have such a high boiling point? It doesn't have any dipole-dipole interaction or hydrogen bonds, just Van Der Vauls interactions and the molecule is pretty round. It should theoretically have a low boiling point. Is it because of its aromaticity?
@nickjonas9222
@nickjonas9222 7 жыл бұрын
agent475816 exactly
@htomerif
@htomerif 6 жыл бұрын
Chemistry aint my strong suit, but could you add something to the aqueous layer to make it more dense and separate easier? Like just more sulfuric acid?
@shitpostfella5528
@shitpostfella5528 2 жыл бұрын
Why is the short condenser needed for the destilation of DCM?
@rockiecoincollecting2890
@rockiecoincollecting2890 8 жыл бұрын
Could you do a video on mercury fulminate?
@FPSproductionsDff
@FPSproductionsDff 7 жыл бұрын
I love your videos, come back please!
@daveb5041
@daveb5041 7 жыл бұрын
"I gave 50 cents to his Patreron to buy some soup. He asked for a dollar; you know what its for!; bottle after bottle of sulfuric acid... he always wants more!"
@ARSZLB
@ARSZLB Жыл бұрын
damn, that temp was climbing SCARY fast...didn't know heating mantles could be so powerful!
@acorgiwithacrown467
@acorgiwithacrown467 7 жыл бұрын
I'm amazed your not a teacher or something, you explain reactions extremely well.
@BillAnt
@BillAnt Жыл бұрын
He's a teacher on YT, so yeah. ;)
@spookywizard4980
@spookywizard4980 8 жыл бұрын
to deal with the water issue, couldn't you add a dessicant to the solution to absorb excess water?
@matze1389
@matze1389 5 ай бұрын
Can i use Xylene as a solvent to get out the MeSalicylate?
@129140163
@129140163 2 жыл бұрын
8:51 That’s the first time I’ve ever heard that name used for baking soda.
@rogerdotlee
@rogerdotlee 8 жыл бұрын
Good lord I have become such a geek. This one had me on the edge of my seat and I was silently cheering when the yield was announced. Now the question is: you stated, repeatedly, that this 'stunk'. Was it because there was such a pronounced presence of wintergreen? Was it overpowering or something?
@thecarrasius
@thecarrasius 8 жыл бұрын
Love your channel, very inspirational stuff. :)
@patricksweetman3285
@patricksweetman3285 8 жыл бұрын
Welcome back, Doug. Did you risk saponifying your ester by stripping off the methanol while the acid and reaction water were still present?
@pragnje
@pragnje 7 жыл бұрын
Its been over a year now, are you alive man??
@henkdevries2002
@henkdevries2002 3 жыл бұрын
is intamolecular fisher esterification in this molecule a possibility? It would form a four membered ring, but that might not be possible due to ring strain.
@ThePaintballgun
@ThePaintballgun 8 жыл бұрын
What are your thoughts on molecular sieves to improve yields? Furthermore what about a dean-stark trap and a carrier solvent?
@johannsiewers6301
@johannsiewers6301 8 жыл бұрын
Is there a way to get stirring with a heating mantle, one which doesn't have stirring by itself Will it work when you put a stirring plate under the heating mantle and control it from there ?
@ZeBeowulf
@ZeBeowulf 7 жыл бұрын
For future reference when you have iron impurities that you need to deal with if add a little bit of dilute HCl to reduce it and make it soluble then add an equal amount of NaOH it’ll precipitate the iron out. In this case it might have destroyed a little bit of your product but it would have saved you the long distillation step. I use this technique for removing iron so that I can run NMR’s, so I know it works well.
@rapunzel_7799
@rapunzel_7799 4 жыл бұрын
Can I make aromatic esters from acid chloride in lab? How do I tackle the HCl fumes? Or do I have to add something to neutralize it?
@extracrazyguy
@extracrazyguy 4 жыл бұрын
Oh doug , 2020 came and you had already departed. that kinda sucks , hope youre alive still.
@anorderedhole2197
@anorderedhole2197 7 жыл бұрын
Doug, if your out there, could you please do some chemistry videos involving wood?
@gabor_kov
@gabor_kov 7 жыл бұрын
Are you gonna make new videos Doug?? I really like you channel. You, Nile red and chem player are the best! I really miss your work ☹
@kinlamyu2982
@kinlamyu2982 6 жыл бұрын
Is it neccesary to remove methanol by condensing or can we just procede to the addition of saturated sodium carbonate solution?
@williamackerson_chemist
@williamackerson_chemist 7 жыл бұрын
Did his ketene lamp blow up or something?
@mmmhorsesteaks
@mmmhorsesteaks 8 жыл бұрын
hey it went lilac. Why is that? Impurities in the drain cleaner?
@DougsLab
@DougsLab 8 жыл бұрын
Yeah. I'm guessing it may have been some carbon particles caused by local superheating because I added the acid rather fast and without stirring.
@atrumblood
@atrumblood 8 жыл бұрын
It was probably some Iron contamination. Iron(III) will complex with the salicylic acid giving a purple solution.
@trustthewater
@trustthewater 8 жыл бұрын
I had the same thing happen using drain cleaner H2SO4. I forgot about it until now.
@zhulsey12
@zhulsey12 8 жыл бұрын
i have done this synthesis before; although i started by purifying aspirin and using HCl (muriatic acid)as my the catalyst. i saw that same purple in the beginning although in my synthesis and it was much stronger. i would agree that it may be because of the extra iron in solution. also i would note that my final product was much much less pure just based on the look and refractive index of it. although i did not drive off the methanol before final extraction.
@AddisonPhilips
@AddisonPhilips 8 жыл бұрын
Attack of the dreaded acetoad !!
@researcherchameleon4602
@researcherchameleon4602 Жыл бұрын
“ALL GLORY TO THE ACETOAD”
@user255
@user255 8 жыл бұрын
Could you use CaCO3 instead of NaHCO3? I mean using CaCO3 and then decant the CaSO4. That way the water layer density would be pretty much 1.0. Edit: oops, I meant Ca(OH)2.
@PerplexedUc9
@PerplexedUc9 7 жыл бұрын
Did ( Doug's Lab ) quit making videos ?
@reecerodriguez3924
@reecerodriguez3924 Жыл бұрын
Organic chemistry students flocking to this video when the semester is almost over..
@verdatum
@verdatum 8 жыл бұрын
Doug! I can't remember if I've asked you this before, and forgive me if I have, but, is there any possibility of doing a video on the Fischer-Tropsch process? I've had the hardest time finding information about doing it in a lab setup, but, I'm no chemist, so I might be searching poorly. Regardless, from what I read, I feel like it's got to be possible; I'm just hesitant to try it on my own, ignorant as I am; and any video I made on the topic would be completely littered with mistakes.
@spookywizard4980
@spookywizard4980 8 жыл бұрын
also, wouldn't the toluene dissolve the salicylic acid as well?
@nivikliriak
@nivikliriak 8 жыл бұрын
I'm a complete layman, but I've been curious about something for a while. I've read that magnesium ions are a Lewis acid, and that Lewis acids will catalyze esterfication reactions. Is there a reason that common magnesium salts (magnesium sulfate, for example) can't be used as an esterfication catalyst?
@kevinbyrne4538
@kevinbyrne4538 8 жыл бұрын
Magnesium is a weak Lewis acid. In at least one reaction, it can be used to catalyze esterification -- but reaction requires the sacrifice of a dialkyl dicarbonate. See -- www.organic-chemistry.org/synthesis/C1O/esters/esterifications.shtm Some magnesium salts (MgCO3) would merely react with the carboxylic acid and form a precipitate (with the evolution of CO2 and H2O). If MgSO4 were a stronger Lewis acid, it wouldn't be used routinely as a drying agent.
@joshsellers5724
@joshsellers5724 7 жыл бұрын
I would love to see somebody like you make a poly aromatic acid from xylene. I wonder if you could use the same method used to make benzoic acid out of toluene. I have loads of potassium permanganate take that then make a polyamine out ethylene glycol and ammonia. then form a polyamide bond between those chemicals. I would throw some change your way, but I'm not far from begging for it these days.
@ZivTheWyrd
@ZivTheWyrd 8 жыл бұрын
gasp! a new dougs lab vidyer!
@skiphoffenflaven8004
@skiphoffenflaven8004 6 ай бұрын
Gorgeous work!
@topherteardowns4679
@topherteardowns4679 7 жыл бұрын
whered ya go? we miss u so. seems like its been forever, that youve been gone.
@StreuB1
@StreuB1 7 жыл бұрын
Yo Doug, where you at?!!?
@FPSproductionsDff
@FPSproductionsDff 8 жыл бұрын
Does the lab smell like wintergreen now? Oh, and excellent video, it was very entertaining and informative to watch. "Now back to non-frog related activities" haha.
@oscarpoll4324
@oscarpoll4324 8 жыл бұрын
Can you make a video on how to make copper phthalocyanine please!
@dominikklinko8015
@dominikklinko8015 7 жыл бұрын
We miss you so much :((((((
@SchizoPost
@SchizoPost 3 ай бұрын
Wish this channel was still active :(
@darellroasa6846
@darellroasa6846 5 жыл бұрын
man ur so good bro. im a marine vagineer 😝 that finds chem. work pretty boring. 1 day I slightly understand how acid/base works and since then i made chemistry my bitch, i love chemistry. thanks man, i really appreciate your work.
@lagerbergn
@lagerbergn 8 жыл бұрын
Isn't the reason why your methanol/water distillate was contaminated with product that the product can be steam distilled and that basically is what your doing when you distill out the water?
@DoRC
@DoRC 7 жыл бұрын
i really enjoyed the relative unscripted feel of this. it seems like everyone is always doing the experimenting before filming and all that gets posted isnl a polished act. i much prefer a more realiatic video.
@italoximenes8755
@italoximenes8755 8 жыл бұрын
\o/ loved the video and the special guest.
@NormReitzel
@NormReitzel 8 ай бұрын
Consider that as yoy distill off methanol, the sulfuric acid is still in the mixture helping equlibrium along. As you distill off methanol, methyl salicylate comes apart and your collected methanol comes right out of your yield..n Better to use a nbig old beaker and sodium bicarbonate, then dump the reaction mixture *quench( into toe bicarbonate. Then there is no acid catalysed equlibrium and bicarbonate is not basic enoiugh to promote alkaine hydrpylsis. I've used this reaction many times in a basic organic lab at UTSA.
@goodsir2551
@goodsir2551 8 жыл бұрын
Hey Doug. PLEASE MAKE MORE VIDEOS PLS PLS PLS!!! *impatience intensifies*
@ashdevos5705
@ashdevos5705 8 жыл бұрын
can you extract neodymium from magnets?
@ficolas2
@ficolas2 8 жыл бұрын
Yes. There is a sciencemadness thread about it www.sciencemadness.org/talk/viewthread.php?tid=66405
@whoeveriam0iam14222
@whoeveriam0iam14222 8 жыл бұрын
amphibian detour at 28:22
@jrnhaugen7122
@jrnhaugen7122 8 жыл бұрын
To avoid spraying you face if you mess up you can vent by using the valve, and pointing it somwhere safe. :-)
@jozsefienciu2325
@jozsefienciu2325 7 жыл бұрын
Hi. You have some idea how to separate k2o from kcl or how to purify k2o from kcl?
@Kadasitimo
@Kadasitimo 7 жыл бұрын
Hey, i don't know how to get the K2O but if you want a good practice you can extract the KCl. First dissolve a whole lot of your fertilizer in water. The K2O will react with water to form KOH and the KCl will stay in solution. Then you add some HCl(based on how much fertilizer you added and on how much K2O or reacted KOH the fertilizer contains). Let it react(KOH + HCl = KCl + H2O), filter the solution of KCl because the fertilizer(I am just guessing)that you are using usually contains a LOT of impurities. Now boil down the solution and that's it. You can get KCl this way but the purity isn't great. You could do a recrystallization but the KCl is too soluable in water. So it's just easier to buy it directly.
@Kadasitimo
@Kadasitimo 7 жыл бұрын
+Jozsef Ienciu Just don't forget to use less HCl or find a way to neutrallize it because boilling a solution with left over HCl can be very dangerous. Be safe.
@swirlingabyss
@swirlingabyss 4 жыл бұрын
You forgot to mention wintergreen flavored dip.
@NormReitzel
@NormReitzel 8 ай бұрын
Also, methyl salicylate will steam distill quite nicelt.
@zacharykokot6625
@zacharykokot6625 7 жыл бұрын
are you still alive? its been 7 months
@berlinblue8899
@berlinblue8899 8 жыл бұрын
Hey Doug, I realy like your videos, but this workup is crapy... (no Offence) Why dont you use a azeotropic distillation? I think this is because you dont have an dean-strak-apparatus. I assume you have a addition funel with a pressure equalizing tube, so the MacGyver way of life would be to use it as the addition funel as a dean-stark apparatus. just take a Roundbottomflask as usual, on top an addition funnel with an refluxcondencer. and than you can do it like normal, but you just need an 1.75 molar excess of your Alkohol (DCM will be your cosolvent) (reff. Oraganikum) and one or two drops of H2SO4 as cat. (prevents dehydration) put about 30ml DCM in the Reaktionflask and about 20ml DCM in the closed addition funnel, and set up for reflux, DCM is ofcause more dense like water so you drip the DCM back in the flask an drive you reaktion to completion! when no more water comes over, put your cooled flask contents in a sep. funnel, wash 2 times with SMAL PORTIONS water, an neutralize it with 5% NaHCO3 (just 5%, so you prevent hydrolysis of your ester), and wash again with smal potions Water. dry it over MgSO4 or some other drying agent and set up for normal or Frak. Distillation to puryfy your Product. I hope this was helpful, and have a nice day^^
@DougsLab
@DougsLab 8 жыл бұрын
No offense taken! My next project is actually an oxalate diester which will be a little harder to drive to completion than simply refluxing with acid. I wanted to show the basics of this reaction before I move on to a more complex setup. Part of the reason this particular synthesis is so easy (as you probably know!) is that this ester is fairly stable against hydrolysis, and this reaction is easy to drive nearly to completion with just a bit of H2SO4, so it works even with a crappy workup! :) I do actually have a dean-stark trap: kzbin.info/www/bejne/ram8qHhsoayBg6s It will be used again to make the oxalate diester, which I have secret and exciting plans for.
@berlinblue8899
@berlinblue8899 8 жыл бұрын
Ohh sorry, you are right. I have not seen it from this didactic perspective. Im happy to see you back on youtube, i kinda missed your Videos^^
@elnombre91
@elnombre91 8 жыл бұрын
I can't see why anyone would ever use a dean-stark for making an ester unless you were trying to esterify a particularly stubborn, sensitive or expensive/late-stage molecule (in which case you might use diazomethane, although It's one of the things I never want to use) as the reagents are so cheap. I don't see a problem with the workup considering it's being done in a home lab setup. It got the product out, right? Also, nice to see you making videos again Doug!
@berlinblue8899
@berlinblue8899 8 жыл бұрын
Rob Newland you are right, but im am chemist too, im am perfectionist, and this is the way I leaned it in the lab, because of the equilibrium and stuf. no doubt, on this it works fine and the reagents are chep bla bla, but as mentionet before im a perfectionist, who wants the hightest possible yield~
@koldfizzion3762
@koldfizzion3762 4 жыл бұрын
You’re awesome. Thank you.
@oscarpoll4324
@oscarpoll4324 8 жыл бұрын
where are you????
@aidanrammy6808
@aidanrammy6808 8 жыл бұрын
when are new videos coming
@jozsefienciu2325
@jozsefienciu2325 7 жыл бұрын
Thank you very much i will try.
@nonohate
@nonohate 7 жыл бұрын
where the fuck is doug, is he dead/severly injured
@lastplace199
@lastplace199 7 жыл бұрын
Iamnyamgamer Apparently his work and home life is keeping him from making videos.
@beneric73
@beneric73 8 жыл бұрын
thanks a lot for the video it was great !
@Hello_Friends
@Hello_Friends 7 жыл бұрын
what is wintergrèen
@rockyrivermushrooms529
@rockyrivermushrooms529 7 жыл бұрын
where you at?
@mrchangcooler
@mrchangcooler 8 жыл бұрын
Am I dreaming or is doug active again?
@misterdrez
@misterdrez 8 жыл бұрын
I love this stuff
@sosses4956
@sosses4956 8 жыл бұрын
How about solving your ether problem with a nice synthesis? :)
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Turning Aspirin into Tylenol
26:01
NileRed
Рет қаралды 2,1 МЛН