[Woopy]

Hello,

I am doing an experiment in which I will have a halophenol, and with KOH in ethanol and an alkyl tosylate, I will need to create an ether.

The first step is to add the KOH and alkyl tosylate, and I should almost have an ether (ring with halogen attached to it and an OR hanging off the ring)

The experiment says after adding those two, I need to reflux the solution for an hour. I don't know why we are doing it..is it to remove the halogen on the ring?

Next we add methylene chloride and water and do an extraction..don't know what this is for.

Finally the methylene chloride is evaporated.

After this we put it through column chromatography with 20% methylene chloride/80% petroleum ether...not sure what this is for.

At what point is this halogen on my ring being removed from the ring?

Not sure what all the extra steps are for if anyone can enlighten me that would be great.

[discodermolide]

You give the impression that you do not know what you are doing at all. The steps you are asking about are the basic techniques of organic chemistry.
As a first step why don't you write a reaction equation for the reaction you are doing? This may help you to see what is going on here.
Google solvent extraction and column chromatography.
Then come back here and let us know what you find.

[Woopy]

Yes, the reaction is written out in the prelab...I can see it

However, the lab doesn't explain why the techniques are relevant to what my goal is. I can't write the reaction because it involves a ring...but I looked at the reaction. It has a ring with an X (representing a halogen) going through the ring as a slash mark (I've never seen this notation before, go figure) so I assume that means the ring still has a halogen on it..and this is after the reaction has been done.

So apparently, what this stuff is the ''work-up'' of the synthesis. I know how to perform the techniques, I know what the purpose is of the techniques, but the thing is no one ever mentions exactly why the technique is relevant to the particular experiment. So yes, I am just blindly following directions and don't know what I'm doing at all.

After I add all the ingredients to get the ring with an X on it, why am I doing the methylene chloride and water extraction? What is there to extract, all I have is a product (I would imagine)?

After I do an extraction of what I think is just product, then I put it through a column to separate stuff. The thing is, what am I separating? If all I had was product from the original reaction, what is there to separate? I suppose this thing might be an elimination reaction..in which case maybe the major and minor product might separate, but that is just conjecture and is probably wrong.

At this point no one has told me how to get rid of the halogen on the ring, because I want an ether ROR which means no halogen on it. So as far as I know I don't even have an ether yet.

[discodermolide]

OK, the X with a line going through the ring means that the substitution point of the halogen is not defined, i.e. it can be in the ortho, meta or para positions. In any case it is not relevant to this reaction as it will not be removed by these reaction conditions.
The purpose of the solvent extraction is to remove any water soluble impurities in the mixture, for example salts. What salt are removed by this procedure?
The column chromatography separates the product from any other organic impurities such as the excess of one reagent or the other, or to remove side products. This is required because no reaction goes to 100% completion, you always get side products and unreacted starting materials.
Why do you want to remove the halogen on the ring? An ether, ROR' can have R = R' as alkyl, aromatic or mixed i.e. aromatic-O-alkyl, which is what you have.
Forget the halogen.

[Babcock_Hall]

Your conditions indicate the existence of a potassium ion, K⁺, which must have a counterion with a negative charge.  At which point in your purification do you separate your product from the potassium salt?