Greetings fellow nerds.
So it's been over three weeks since my last video and i vow to keep you updated as to what i'm up to.
I've been very busy these past weeks but it's a good kind of busy.
First i spent a couple of weeks doing chemistry for a TV show.
I'll be honest, I look like an idiot.
And not the endearing kind, but the stupid and pretentious kind.
As the old saying goes, better to remain silent and be thought a fool than to speak and remove all doubt.
Anyway, if that TV show goes to air i'll let you know so you can cringe at how pretentious i sound.
Moving on i've been doing alot of chemistry and not all successful.
First i needed to replenish my supplies of ethyl propionate and trimethyl orthoformate.
Now i already showed you how i made them but i want to show some alternative methods for didactic value.
In particular i tried to make ethyl propionate by the amide approach.
Basically, convert propionic acid into propanamide, then react propanamide with ethanol to make ethyl propionate.
In theory this should give higher yield because the ammonia product is very volatile compared to water.
It should boil out and thus drive the reaction forward as it's lost.
So i tried making propanamide by reacting urea and propionic acid and that seemed to work somewhat.
I had a lot of condenser clogging problems due to ammonium carbonate solidification but that was to be expected.
Once i had the propanamide i added ethanol directly refluxed and tried to distill off the ethyl propionate product but there was none.
I probably needed an alkaline catalyst.
So i added some sodium hydroxide and tried that but that didn't work either.
I'll be honest i was a very reckless and haphazard with my approach and didn't bother purifying the propanamide before i added ethanol.
I know the process does work since it's in the literature, but it appears you actually need to put the work in and properly purify the reagents as you make them.
I wanted to see if this process was better, easier or faster than the molecular sieve approach i showed last year.
It is not.
If the molecular sieve approach does everything, requires very little effort and actual work, and still gives awesome yield, then there is really no point in wasting time on other methods.
So after spending a week on it i abandoned the project.
We have more interesting things to try.
Next i made trimethyl orthoformate to replenish my supplies.
I didn't film it though since it was pretty much the same as my old trimethyl orthoformate video.
However, i did change the procedure a bit and instead of using molecular sieves to make sodium methoxide i used sodium metal.
It's faster and higher yielding than using molecular sieves.
Since i need to make another batch anyway let me know if you want me to film it this time using the sodium metal approach.
I'll be honest, the individual parts to the procedure are nothing you haven't already seen before.
They're just being put together differently.
So moving on to the main attraction, making alkali metals.
You've already seen me spend a long time making alkyl halides and then performing grignard reactions to make medium and heavy alcohols.
These are catalysts to making alkali metals by the magnesium reduction method.
The advantage of using catalysts is they should work under mild conditions and you don't need to set things on fire.
The amateur community was already very successful in making it work with potassium but not sodium.
So i tried doing it with my favorite solvent for this process, tetrahydronaphthalene.
I had good success with it several years ago when i was making potassium but found it didn't work with sodium.
I redid my procedures and again failed as before.
But this time i thought it was because my tetrahydronaphthalene was impure.
It did have a yellow tinge so to purify i used sodium destruction.
This was not something i had amateur access to during my initial experiments.
Sodium destruction works with all kinds of inert solvents like ether, mineral oil, even triethyl amine so i thought it would work here.
I refluxed with sodium, got tar that i presumed was the impurities and then distilled.
I used this purified tetrahydronaphthalene for further experiments but again i failed.
After several days of failures i was starting to suspecting the solvent so i put fresh sodium in and refluxed..
Then i found the culprit.
More tar kept coming out.
The tetrahydronaphthalene is either grossly impure, or i suspect, the tetrahydronaphthalene itself is reacting with the sodium.
It's not so inert afterall.
Now the reaction seems to be extremely slow and produces only tiny amounts of tar even after several hours of refluxing.
So for the most part tetrahydronaphthalene is considered inert.
But when working with a catalytic reaction even a small amount of impurities or tar can destroy it.
Whatever the case may be, persistent impurities or reactive tar formation,
Any sodium made would be destroyed again.
I'll discuss this further including why potassium seems to work once i finish my alkali metal research.
For now though work is still in progress.
I'll either get sodium metal by the catalytic approach, or have a comprehensive failure analysis video for you.
So that's what i've been up to for the past three weeks.
Hopefully the next couple will actually have a proper video on something.
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