Ok, this is the one we've been waiting for.

Vanillin demethylation using Fioria.

Here's our trio of ingredients for the reaction.

Starting on the left, we've got 20 grams of freshly prepared anhydrous aluminium chloride.

We used the process we've covered in a previous video, but here's a very quick recap.

We started with 70 grams of anhydrous zinc chloride and 14 grams of aluminium powder mixed together well as you can see here.

Then this goes into a clean dry flask and is heated very strongly.

Using a large gas flame.

Soon the reaction starts up and then suddenly large amounts of white smoke are generated.

These pass into an ice chilled large bottle where they condense.

And there we go.

Anhydrous aluminium chloride powder which is light and fluffy and looks a bit like snow.

Keep it protected from air using a plastic film.

Now for our second ingredient.

This is 20 grams of vanillin crystal which we dried in a desiccator for a week over calcium chloride.

And last but not least, 11.4 grams of Fioria.

We managed to find an online seller for this compound and got hold of some.

We expected it to have a really nasty unpleasant aroma.

But actually it's just boring odorless white smoke.

It's crystal.

No scent at all.

Let's start with the vanillin.

We need to make this up into a solution.

Here's 40 mils of dried dichloromethane.

We'll start with this and add more if we need to.

We've got a clean dried beaker set up on the hot plate stirrer.

First of all we add the vanillin crystal.

And now the DCM.

And we get stirrin to dissolve.

As the vanillin dissolves, the mixture cools very strongly.

So much so that interestingly, at a certain point after a lot has dissolved,

it seems to then cool enough for everything to recrystallize back out again.

And stirrin fails.

We add probably about another 25 to 30 mils of DCM and after a while everything goes into solution.

We cover this up and reserve it for later on.

Okay, let's get set up for the reaction now.

Here's the setup we're going to be using.

You could improvise differently, but you need a dropwise addition and a reflux condenser.

We're using the 500 ml two neck flask.

And strong stirrin is really important.

On top of the flask we've got a pressure equalized addition funnel.

With the condenser on a regular one will also work.

And on the side neck of the flask we've got a nice sexy dime rose condenser.

Note that all the glassware was acetone washed and dried carefully before use.

And the cooling water needs to be quite cold as the DCM solvent is low boiling.

All systems are go.

And on top of the condenser we've got the made shift calcium chloride drying tube to stop moisture getting in.

We've removed the addition funnel temporarily.

So let's lock and load.

Firstly our solvent.

We're using 80 mils of dry dichloromethane.

Once this is in we'll get the DCM solvent.

Stirrin vigorously.

So first, our anhydrous aluminium chloride.

Here we are all in.

Sometimes this turns a strange color, but this time it's just a pure white suspension.

Now for the file area.

Okay everything's in and we've put the addition funnel back on.

We've also started gently heating the mixture.

Just enough for a very slow reflux.

After about 10 minutes the mixture seems to have formed a suspension.

If we stop stirring just for a moment.

Two liquid layers actually become visible.

We're not sure what this is.

Possibly an addition complex of the file area and aluminium chloride.

We leave this stirring for another 20 minutes.

Half an hour in total.

Okay now for our vandalin solution in dichloromethane.

This goes into the addition funnel.

Here we go.

Now we start the slow addition of the vandalin solution into the reaction mixture.

The faint yellow color immediately starts to form.

We keep the gentle reflux going in the flask.

Let's stop stirring for a moment.

You can see that a precipitate seems to be forming as the drops enter the mixture.

We're just going to leave this slowly adding dropwise with stirring and with a very gentle reflux.

Soon a slightly orange color starts to form.

And then a monster appears from the depths.

A yellow viscous goo starts to be created.

At a point this makes stirring difficult so you need to adjust the speed a bit so it's still going okay.

And we continue with the slow addition.

After a while the yellow goo turns an orange color.

Okay addition is complete.

This took an hour and half in total.

We removed the addition funnel but save it because you'll need it later.

We then took a metal rod and scraped up the lumps of goo in the mixture so that they were actually able to be stirred around.

Still a gentle reflux going on.

So now we leave this stirring and refluxing for a further two hours.

Over this time the mixture gradually changes and becomes a darker red color.

Still with a lot of yellow solid in there as well.

And the lumps of goo start to break down and form a homogenous mixture again.

After two hours the color is a dark red.

At this point we switch off the heating but continue to allow the mixture to stir.

And we leave it stirring for eight hours overnight.

In the morning it looks pretty much the same.

A dark red color.

So we stop stirring and chilled the flask down ready for the next step.

We now need to add dilute hydrochloric acid which will hydrolyze any complexes formed in here.

And separate our product.

We've placed a clean addition funnel back on top of the flask.

And now we'll make up the dilute hydrochloric acid solution using 15 ml of 36% acid and 40 ml of water.

Water goes in.

And then the acid.

Here we go.

Next we place this in the addition funnel on top of the flask.

We're also using a cool water bath just to make sure that the DCM remains cold and doesn't boil.

Okay let's start dripping in the aqueous acid.

This takes about 30 minutes to complete.

And as the acid goes in the mixture turns yellow and then clumps of orange material form in the mixture.

We're done now so we remove the funnel and then get the mixture stirring vigorously.

After 30 minutes you may have some stubborn lumps of orange goo which still won't dissolve.

If so, take these out and place them in a small beaker.

And add a bit of dilute hydrochloric acid and break them up by hand.

They should dissolve.

Get this solution back into the flask and stir for another 15 minutes.

We've got two layers now.

An upper aqueous layer and a low DCM layer.

So we get the contents of the flask into a separating funnel.

First we'll separate the two layers into different beakers.

That's the DCM.

And now the aqueous layer.

Here we go.

First thing we'll do is get the DCM layer back in the funnel.

And wash it with 30 ml of water to make sure we've got as much product out as possible.

We drain the DCM and then transfer the aqueous layer to combine with the upper one.

Okay we've got an aqueous solution hopefully containing our product.

So we place this into the funnel and now we're going to extract this three times.

Each time with 30 ml of ethyl acetate as the solvent.

This forms the top layer.

After really thorough shaking for a couple of minutes we allow to settle.

Then drain off the aqueous layer.

And then separate the ethyl acetate into a clean flask.

Here we go.

Now place the aqueous layer back into the funnel and repeat two more times with 30 ml of ethyl acetate.

The organic layer becomes pale.

We'll hang on the aqueous layer just in case.

But let's work up the ethyl acetate solution.

First we add a little anhydrous magnesium sulfate to dry it.

Then we decant the liquid into a clean dry flask and set up for distillation to remove the solvent.

We're going to use a hot water bath.

too much heat on the product.

We've seen before that it tends to turn red when heated

above about 50 degrees.

Here's what we were left with. The red oily liquid which on cooling became very

viscous

Well even if this contains our product

there's only around 2.5 grams of it, which isn't great.

We did a couple of experiments to see if we could get impurities to dissolve

out and crystal the product to form, but no solvents including ether,

ethanol, acetone or DCM would do this.

So we mixed up a saturated sodium bisulfite solution

aldehyde bisulfite adduct to form. And it did. So we filtered this off.

It was difficult to wash, but we ended up with about 4 to 5 grams of crystalline adduct

which we're assuming is the protocatetudeldehyde adduct. Still quite brown and dirty though.

Not really enough here to do anything with though.

So all in all this is a disappointment. Again we're getting about 10% yield or less of a dirty

impure product. In fact the product from the last pyridine run was much cleaner.

We're not sure what it is we're doing wrong here. Whether it's the reaction itself or the workup.

We'll keep investigating but we'll hold off perfuming this again until we've got a good

theory as to what is going wrong. Let us know if you have any theories. In the meantime,

stay tuned for some other reactions.