Sciencemadness Discussion Board

Ethyl Acetate -> Ethanol

haribo - 16-2-2009 at 09:37

Before someone flames me for such a basic post, this has been done in an alkali (NaHCO3) enviroment so as to remove the acetic acid from the system. My problem is that there is still a trace of AA in there. Where I am, ordering pure ethanol ALONE is suspicious and the AA will mess up my experiments on using ethanol for unusual borohydride reductions (zinc, pottassium and so on).

Thoughts (beyond I'm an idiot!)

Picric-A - 16-2-2009 at 09:59

Refluxing the ethyl ethonate in a exess of NaOH solouion will completly break down the ester.
Maybe your problem is the NaHCO3 isnt alkaline enough or you arnt giving an exess.
you are trying to swing the equation to the left, and by using an alkaline enviroment you will do that,
If you try and do the same in water (weak alkaline enviroment), it will probably take a long time and you will end up with a 50/50 mix of ethyl ethonate/acetic acid-ethanol.
CH3CH2OH + CH3COOH ⇌ CH3COOCH2CH3 + H2O
Its weird you cant buy ethanol but you can buy ethyl ethonate.... are you using nail varnish remover ethyl ethonate? if so you are better off starting with methylated spirits, the nail varnish remover contains lots of isopropyl alcohol impurities amongst other things....

[Edited on 16-2-2009 by Picric-A]

panziandi - 16-2-2009 at 11:55

Can you get NaOH? If you can't heat your NaHCO3 in a crucible to give Na2CO3, a solution of this will hydrolyse your ester although the usual technique, and the one I would recommend would be NaOH or KOH.

If there is AcOH in your EtOH it whould be removed when you dry your ethanol. Using CaO or Mg to dry your EtOH with remove any AcOH. If you have free AcOH in your EtOH product, then I would be positive you have unhydrolysed ester in there too which will **** up your reductions too :P ... try:

1) Using sodium carbonate or sodium hydroxide
2) Reflux for longer
3) After redistilling your ethanol dry it using Mg or CaO

Bolt - 16-2-2009 at 21:34

Check your pms, haribo!

chemrox - 16-2-2009 at 22:44

I don't know where you are but surely you can get 100 proof (50%) alcohol. Here they sell 98% at the Liquor Store. Either of these can be dehydrated. I'd be truly amazed if there weren't soap makers where you are .. and what about biodiesel?

Ebao-lu - 16-2-2009 at 23:58

maybe distillation over some dissicating agents (like NaOH with no water, Mg(ClO4)2) can absolutate ethanol? Otherwise, if you want to remove traces AA, are you sure distillation would not help?

Bolt - 17-2-2009 at 00:31

I think this was already said... but in plain terms, if you use an excess of a strong base, to convert all the acid to its salt, you may then distill over your ethanol/water azeotrope without fear of acid contamination.

[Edited on 17-2-2009 by Bolt]

Ebao-lu - 17-2-2009 at 05:32

Sorry, i thought there is a problem with absolute ethanol buying, but now i realized any ethanol is a problem. Maybe distill it from some alсo drink? It would be better to dry the product with that NaOH, rather then wasting it for ester breakdown(1mol NaOH per 1 mol ethylacetate, 400g NaOH per 460g ethanol). Better even to use acidic hydrolysis with ethanol distillation(as aseotrope), and remove AA from it with NaOH

unionised - 17-2-2009 at 13:57

I really wouldn't try drying ethanol (or any other organic material) with Mg(ClO4)2.

Since you are going to need to distil the product you might as well start from methylated spirits or vodka and distil that.
Complete hydrolysis of the ester is easier if you use a stronger base, but you risk getting condensation products.

starman - 17-2-2009 at 15:55

off topic but the same reaction.... If you wanted to maximise and recover the acetic acid with the target being GAA?

haribo - 18-2-2009 at 04:16

The problem is that to make ethanol undrinkable they add quite a lot of crap to it and since I'm messing with different hydrides, I really don't want anything except alcohol. 99.95% ethanol is suspect if bought in any kind of bulk.

When I have finished classing one agent (potassium borohydride is used in huge amounts in some kinds of paper making for example) I will do a thread for each

So far, the most funky/cool/amazing agent is STAB (sodium triacetoxy borohydride). That 1-pot fentanyl route is just so cool. OK, only 40% yield bit even so, swap the 4 piperidone for 3-methyl 4-piperidone and you have a winner.

panziandi - 18-2-2009 at 06:40

Haribo are you making paper using KBH4 or are you making fentanyl analogues using STAB? If you are in the UK you should be able to get ethanol easily, even methylated spirit can be purified more easily than ethyl acetate. Who uses sodium bicarbonate top hydrolyse esters, you seem like a k3wl. I think your drug post interests are better suited to other forums?

haribo - 20-2-2009 at 08:53

STAB is basically insoluable with H20

What we need something that you can buy 50 Kg bags.

BobHawson - 14-3-2009 at 12:27

I don't know of any fentanyl synthesis using STAB.

If the author merely wants to get drinkable ethanol, I imagine buying imitation almond extract, adding sodium bisulfite, then cooling and filtering the liquid would leave you with ~38% ethanol and water. Possibly traces of biuslfite, but it shouldn't do harm as its used in food and wines.

greenyppols - 23-10-2009 at 17:05

Why go backward from ethyl acetate to ethanol?

what's wrong with a simple fermentation of sugar and some yeast, dump a fining solution to settle the yeast to the bottom, decant the clear alcholol/water mix, and distill???

Try some homebrewing? It works wonders, its limitless (well..there's the stuff to make it), and way way way cheape than buying the heavily-taxed bottles of commercial booze just to concentrate it...

A six gallon carboy..four pounds of sugar, water and specialized yeast available on the 'net will yield nearly 4 liters of 95% ethanol...so long as you can wait a week for the fermentation to take place. With all the expenses, prolly $30, but its a one time expense and after that, its free as far as Im concerned....

just my 2 cents.....

[Edited on 24-10-2009 by greenyppols]

bbartlog - 23-10-2009 at 18:21

maybe distillation over some dissicating agents (like NaOH with no water, Mg(ClO4)2) can absolutate ethanol?

I don't believe NaOH is a good choice; isn't it slightly soluble in ethanol? Though if you're talking about passing the vapors over/through dry NaOH it might still work. Still if you're going to go with desiccation I think just putting MgSO4 or Na2SO4 in after distilling to somewhere upwards of 90% would be easier. Those desiccants are also easy to redry whereas NaOH starts to pick up CO2 from the air if you try to just bake it dry again.

A six gallon carboy..four pounds of sugar, water and specialized yeast available on the 'net will yield nearly 4 liters of 95% ethanol

You're omitting the distillation step, though. I do plan to try this, but I'm currently geared to distill only one liter at a time, which will make it kind of painful.

vulture - 24-10-2009 at 06:30

Do NOT distill any flammable liquid over Mg(ClO4)2 unless you want a major explosion.

grind - 26-10-2009 at 22:32

Quote: Originally posted by haribo  

STAB is basically insoluable with H20

I´m afraid that is not correct. STAB is completely soluble in water, but with decomposition into sodium borate/acetate and acetic acid (and of course hydrogen).
Ethanol is not suitable as solvent for STAB reductions, decomposition is the reason too.
By the way, panziandi is right, wrong forum for interest in producing drugs.

Vogelzang - 27-10-2009 at 14:19

This looks like an interesting process for making ethyl acetate from CA4:905 if you wanted to make ethyl acetate.

CA4-905.jpg - 106kB