[dodopa]

Hello,

I´d like to ask you about advice how to prepare 1,3,5-triethylbenzene from benzene. Any idea?

Thanks a lot.

[Babcock_Hall]

According to the rules of this forum (see red link above), you must provide your thoughts or show your attempt before we can help you.  A possible place to start might be to indicate why some attempts to make this compound will fail.

[dodopa]

Hello, I´ve only found this https://books.google.sk/books?id=l9dhDwAAQBAJ&pg=PT1002&dq=1,3,5-triethylbenzene+synthesis&hl=sk&sa=X&ved=0ahUKEwiusc2IxpjdAhU0wAIHHTzUBNIQ6AEIKTAA#v=onepage&q=1%2C3%2C5-triethylbenzene%20synthesis&f=false

But I´m bit confused because of Friedel-Crafts alkylation in m-position when I have ethyl group which is o-,p- director.

Thanks.

[wildfyr]

What about making something with the same number of carbons as ethyl, but a different function group that can be later converted to ethyl?

[dodopa]

Yeah of course, but I know, that deactivating groups, which are meta directors are limitating in F-C alkylation.

[Babcock_Hall]

Do you have a particular group in mind?

[dodopa]

What about making something with the same number of carbons as ethyl, but a different function group that can be later converted to ethyl?

With same number of carbons, first opinion in my mind is carbonyl group, but I think, it will be not working very well...

[Babcock_Hall]

I don't know how serious the problem of deactivation will be.  If this is a homework exercise, I might supply an answer and qualify it in that regard.

[dodopa]

I´m sure, that this option is not right. Solution must be a little bit complicated :/ ...

[wildfyr]

I'll just spit it out since we all have the gist and say use ethanoyl chloride with FeCl3 for a Friedel kraft. I think such a reaction works, you just have to do it under pressure and high heat. Especially if this is homework and not a real bench question.

I can think of another way but it's a little sloppy too.

[rolnor]

Can you really make 1,3,5-triacetyl benzene with FC?

[spirochete]

According to wikipedia (and I think I also read it in March's Advanced organic) you can run alkylation reactions for a long time at relatively high temperatures and eventually the meta product is favored. The 1,3,5 product is the thermodynamic product for steric reasons. It forms more slowly, because the carbocation intermediates are not as stable as ortho and para products.

That's what it says here for making 1,3,5 triethyl benzene: https://en.wikipedia.org/wiki/Friedel%E2%80%93Crafts_reaction#Friedel%E2%80%93Crafts_alkylation

It looks like OP maybe linked to a book stating this. But I can't read it because it's not in english.

Most introductory students should be careful because that product would likely get you the "wrong" answer on a test!