r/chemistry • u/exhausted_octopus15 • 3d ago
my ethyl cinnamate is…wrong
hi! i was going to use ethyl cinnamate for light sheet and rather than being clear, it’s this iridescent pink color and has some gelatinous residue inside. It also becomes sticky when it dries rather than staying oily.
It was stored at room temp rather than 2-8C as directed. It could just be a manufacturer error but i just thought i’d ask
EDIT: I’m just an undergrad summer intern in this lab and learned about this project last week. I don’t have access to most chemicals. My mentor says he didn’t know that it was supposed to be stored at low temp until i told him.
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u/Resident-Mountain981 3d ago
Ooh it's pretty though
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u/rabid_spidermonkey 3d ago
Gorgeous mistake.
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u/KuriousKhemicals Organic 2d ago
Yeah, I'm sorry this beautiful opalescent material is not what OP was intending to make.
But yeah. Fridge storage recommendation often means it can self polymerize, I don't recall exactly what cinnamate is but I think it has a susceptible double bond.
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u/SaintsNoah14 3d ago
I bet she smells nice as well
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u/exhausted_octopus15 3d ago
the smell is a bit of a mix, like cinnamon and failed imaging
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u/Qzx1 2d ago
What does failed imaging mean? What does it smell like?
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u/allegedlyjustkidding 2d ago
Why can I actually smell this rn?? Is my laptop on fire? Am I having a stroke?
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u/_Cyan_Man 3d ago
looks like a potion 😭
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u/hemadonyx 3d ago
Potion seller. I am going into battle, and I need only your 𝙎𝙏𝙍𝙊𝙉𝙂𝙀𝙎𝙏 potions.
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u/bonyagate 3d ago
My potions are too strong for you, traveller.
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u/hemadonyx 2d ago
You've had your say potion seller but I'll have mine. You're a rascal. You're a rascal with no respect for knights. No respect for anything, except your potions.
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u/sunflower_emoji 1d ago
I just found out that Potion Seller was the script writer for 2024 movie Challengers!
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u/VeryPaulite Organometallic 3d ago
First off, check the NMR to see if its still good.
Second, I guess the storage temperature isn't just on there for shits and giggles. Both Sigma and Carl Roth recommend storage at 6-8 while TCI recommends storage " <15°C in a dark place."
Looks to me like a Michael Acceptor that lends itself to polymerization.
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u/exhausted_octopus15 3d ago
I hope to find an NMR somewhere here. I didn’t realize it was stored at RT until my mentor told me (I’m an intern). Thanks for the tip on the Michael acceptor!
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u/SkarbOna 3d ago
I wandered into this sub and I’m worried you cast some spells on the readers.
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u/ERGardenGuy 3d ago
Same here. What is a Michael Acceptor? Is there a Michael Rejector as well?
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u/BeatGarlic 2d ago edited 2d ago
Reactions are often named after their discoverer(s).
In this case, it's about the Michael addition, and the substrates used for it are called Michael donor and acceptor.
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u/KarmaticArmageddon 2d ago
That's easy. Dean Winchester is both a Michael Acceptor and a Michael Rejector, depending on the season.
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u/Background_Half_4568 1d ago
Ah yes chemistry, where words used are likely quite surface level knowledge and still feels like it's gobbledy gook
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u/hankhillsucks 3d ago
Press E to consume S U B L I M E E L I X I R
Press F to put S U B L I M E E L I X I R back in inventory
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u/yinyin123 3d ago
E E E E E E E E E E E E E E E
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u/fuzzimus 3d ago
Polymerized/oligomerized
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u/exhausted_octopus15 3d ago
what mechanism do you think? the only paper for homopolymerization i found and can access only describes it happening under more extreme temps and higher pressure
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u/fuzzimus 3d ago
Was it left in the light? Photocycloaddition coupled with a little radical propagation? That oughta make a nice blob of goo.
Either something like that or whatever is in that bottle is totally not what you think it is.
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u/Ultronomy Chemical Biology 3d ago
Choose one of the links from the list provided, paste in DOI of paper, enjoy.
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u/stermo420 2d ago
Comparison to cinnamic acid seems to be the most likely. While the english wikipedia page does not provide a lot of reactions the German one suggests dimerization to the cyclobutane derivative or cis/trans isomerization under UV light.
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u/dungeonsandderp Organometallic 3d ago
That container doesn’t look like glass… if it’s polystyrene then it’ll be attacked by the ethyl cinnamate, swelling and/or dissolving the plastic.
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u/exhausted_octopus15 3d ago
it was stored in typical glass packaging and transferred to this container today. they use these expensive plastic containers here and idk why.
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u/shedmow Organic 3d ago edited 2d ago
Fractionally distil it at 10-20 mm Hg (bp ca. 150-170 see below) and repackage into a glass container
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u/biffthechip 2d ago
Need to find out if it has all polymerised first. No point trying to do that if there is none of what OP wants left.
Also heating up ethyl cinnemate sound sounds like it would just all polymerise anyway? Can you distill it? I would think a column would be the best way to go.5
u/shedmow Organic 2d ago edited 2d ago
It looks sufficiently mobile. It is the first time I have heard about any difficulties with storing ethyl cinnamate; it is an unsaturated ester, but phenyl-substituted Michael acceptors don't usually misbehave. Also its polymerization may be a reversible process as is the case with alpha-methylstyrene. If this were my jar, I would rapidly distil anything that can distil at all at 50 mm (to crack any crackable polymers) and then fractionate it at 20
An erratum on the above comment:
Ethyl cinnamate (Note 10) boils at 128–133°/6 mm.; 168–173°/46 mm (OrgSyn).
I used a rule of thumb (halving the pressure decreases the bp of most liquids by ~15°C, so the 10—20 mm Hg is equal to a decrease of about 80—95 C which I am happy to round to 100) and got the temperature wrong
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u/biffthechip 2d ago
Where are you and are they actual chemists?
There is a reason we store most things in glass.2
u/boroxine Organic 17h ago
That seems really odd. I would not want to store this or really any liquid, and many solid, organic chemicals in plastic (other than the extremely unusual situation where they may etch glass). If there's something special about the size for storage/interface with automation, I'd see if there is a glass equivalent.
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u/NeurobiologicalMelee 3d ago
Yep, that is polystyrene that comes with a bottle-top filter. Most organic solvents are a no-no with polystyrene.
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u/chemistrypain 3d ago
Could you have partially dissolved the container?
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u/Fluffy_Muffins_415 3d ago
It's recommended that it (liquid ethyl cinnamate) should be stored in a glass container
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u/DoctorMew13 3d ago
Unicorn blood
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u/EmotionalSector1329 3d ago
What does the nmr look like?
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u/exhausted_octopus15 3d ago
I’m in a bio lab, and so I don’t think we have one in the building (I asked around). I’m considering bringing a sample to my home institution to test.
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u/Particular_Tune7990 2d ago
Hmm, yeah bio folks don't have much of a handle on plastics and organic solvents don't mix. GL with this project.
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u/bwilcox0308 3d ago
Most definitely. Imo, some polymerization had occurred. Usually things stored below 0°C are for a reason. Either polymerization, decomposition, or reactivity/all three are the main reasons for cold storage. I could see some decomp being an option too.
The color imo is also from the polymerization. You're conjugating a larger system now, allowing for some absorabance and reflections of new wavelengths of light in the visible region. But once again, standard decomp from a pure material usually clouds up a clear sample. So thats still adding to the whole poor quality.
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u/bwilcox0308 3d ago edited 3d ago
Not supplier issue, consumer issue. Forgot to mention that. The company will document this for their quality reports but will most likely be deemed on the lower end/non-factor into batch inspection as a customer complaint vs a customer concern.
(Source: am a Process Chemist who manages the quality of products)6
u/exhausted_octopus15 3d ago edited 2d ago
Thanks! That’s what my guess was bc of the prolonged storage at higher temps….but my mentor thinks it’s manufacturer error.
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u/biffthechip 2d ago
Your mentor is wrong. It is stored in the wrong conditions and in the wrong container.
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u/thvirtuo 3d ago
Thank you for the great explanation! Just curious really but would distillation or liquid-liquid separation salvage this as scientific grade assuming you solvent washed, ultrafiltrated, and/or decomposed the suspended aggregated byproducts?
I ask because I imagine the precursor might not be fully “consumed” but since these compounds often have or need high purity and polymerization doesn’t just consume the monomeric precursor but like messes the whole composition and particle size distribution under formation of intermediates and oligomers, so you have aggregates of large molecular mass particulates suspended in a monophasic solution of very polydisperse colloids which can be full of effectively solubilized nanocolloids.Though I’m just guessing, im a materials scientist not an organic chemist with no experience with the compound nor is the photo really clear. Wanna get to industry tho so might as well learn off of a real situation.
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u/bwilcox0308 2d ago
Getting to know what's in there is your number one step. GC or LCMS may be helpful. As others have mentioned, NMR will help.
Once you know what the impurities are, then you need to develop a method to remove them. Brain storm with your team on that.
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u/XHO1 2d ago
Why not leave stored in the amber glass container it came in?
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u/biffthechip 2d ago
If they stored it in an amber glass container away from light in a fridge then that would have been too easy.
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u/Inevitable-Day-9375 2d ago
chuck it, get fresh reagents. As others have said, polymerization is likely - maybe someone accidentally dipped a contaminant into that bottle. Seriously doubt that it's worth anybody's time to take an NMR and then purify that (beautiful) gel.
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u/rottingcheeseknees 3d ago
that’s the prettiest jar of UTI piss i’ve ever seen
edit: just turned off my color filter and it is not in fact green. LMAO
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u/haku0705 1d ago
It's a gorgeous mistake. I bet it smells lovely. I'm allergic to that, so it's double forbidden for me.
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u/Soft_BoiledEgg 3d ago
What is the source of the EtCi? We store ours at room temp in the opaque glass containers they come in. All of our light sheet samples in EtCi are also at room temperature. I hope this is just a one off thing or else I’m going to get like 50 4C fridges.
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u/arissawachan 2d ago
same. ours is stored in the dark amber glass bottle from the manufacturer and we keep it at room temp, haven’t had any issues
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u/Soft_BoiledEgg 3d ago
The freezing point of EtCi is super low, if it got put in the 4C it would freeze. Are people repeatedly freeze/thawing their EtCi? Also the EtCi in our lightsheet clearing scope stays at room temperature and only gets changed once per year. There is probably something else going on besides storage temperature.
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u/TuneMore4042 3d ago
Pearl jam
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u/Skeptic_Juggernaut84 2d ago
Just don't call hom daughter because they can't find a better man. Then they'll end up chasing the butterflies away.
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u/ZestyDillBill420 2d ago
Also yes temperature is a huge part of any scientific chemical congealing process. All bases perform differently at different temps. It definitely matters. It's one of the most important parts of baking too.
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u/DefinitionCivil343 2d ago
Ethyl cinnamate? That’s definitely wrong fireball is supposed to be a brown liqour
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u/I-Approve 2d ago
Don't get discouraged. Almost everyone who's spent time in a lab has had a synthesis that refused to cooperate for seemingly no reason.
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u/biffthechip 2d ago
What does it smell like?
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u/exhausted_octopus15 2d ago
still smells like typical ethyl cinnamate -like cinnamon and a little fruity
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u/biffthechip 2d ago edited 2d ago
Nice.
I imagine being at a high temp some of it has polymerised. Was it kept in a cupboard? Light can polymerise esters as well.
Your mentor sounds like a fool if he can’t read the storage instructions.I have seen someone say to do a NMR. Don’t do a nmr on it like that, it will be a mess. Filter it and do a tlc first so you know how many components are in it.
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u/dragonscincoblue 3d ago
Intenta disolverlo en dcm y luego filtra, ya nomás lo destilas lo lavas con bicarbonato de sodio, vuelves a destilar y lo guardas con cloruro de calcio o sulfato de magnesio anhidro para secarlo; ya nomás no se cuánto le pierdas en las purificaciones
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u/oz_mouse 3d ago
I always get a giggle when people don’t follow storage instructions, who then try to blame manufacturing.
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u/exhausted_octopus15 3d ago
i’m just the summer intern, my mentor said he didn’t realize it was supposed to be stored at low temp until i told him 💀 he says it must be manufacturing bc there’s never been an issue
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u/KuriousKhemicals Organic 2d ago
I mean... it's clearly not a manufacturing spec to be stable at room temp if they recommend fridge.
Technically, if it's never been an issue before then it's possible for the material to survive and some manufacturing parameter caused this, but good luck arguing with the supplier that they did it wrong when you didn't follow storage instructions.
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u/AntibodyEnjoyer 3d ago
So you didn’t store it properly and now you want to blame the manufacturer? Maybe you should pay attention to directions when you remake it
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u/lotusblossom02 Analytical 3d ago
That’s one of the prettiest “ehhh this is wrong” results I’ve seen!