Styrene Derivatives by Aromatic Chloroalkylation

[Rhodium]

https://www.thevespiary.org/rhodium/Rhodium/hive/hiveboard/picproxie_docs/000468021-file_7khg.gif" title="View this image">

Chloroalkylation of Phenol Ethers & Synthesis of Methoxystyrenes (Part 1)
Raymond Quelet

Bull. Soc. Chim. France 196-205 (1940)

(https://www.thevespiary.org/rhodium/Rhodium/pdf/chloroalkylation1.pdf)

Chloroalkylation of Phenol Ethers & Synthesis of Methoxystyrenes (Part 2)
Raymond Quelet

Bull. Soc. Chim. France 205-215 (1940)

(https://www.thevespiary.org/rhodium/Rhodium/pdf/chloroalkylation2.pdf)

[imp]

Thank you Rhodium.

So, what do you think about 1,2-methylenedioxybenzene to isosafrole?? SWIM is curious to hear your opinion.

Maybe that Friedel-Crafts reagent is going to cause some cleavage. Also, the yield would be quite low unless we can make some 'improvisations' to the reaction.

[Rhodium]

It's possible... If the MD ring cleavage would be too great, then one could just switch to a milder Lewis Acid like TiCl₄ and try again.

[ning]

Then the supported-ZnCl2 direct allylation method just got even easier, by removing the need for the supported Na2CO3! Grrrrreat!

[imp]

SWIM sees a couple of obstacles...

1. The paper by Quelet says that dehydrochlorination is done using pyridine. If we had pyridine in the first place, then eugenol --> safrole would be a much better idea.

2. We need to buy/make 1-propanal.

Once SWIM saw the dreaded 'p' word (pyridine) in the article, her/his heart just dropped   . Is there any other way to dehydrohalogenate that chloropropyl group?

[Rhodium]

This works, but will instead yield propenylbenzene:

https://www.thevespiary.org/rhodium/Rhodium/chemistry/allylbenzene.html