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Need help with a past paper question please!!!

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The q asks for the reagents and conditions required, plus the name of the reaction needed for step 5, so to convert compound D to ibuprofen.

I'm so confused :frown:

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Reply 1

charco

Study Forum Helper

Original post by 3mma_gal96

The q asks for the reagents and conditions required, plus the name of the reaction needed for step 5, so to convert compound D to ibuprofen.

I'm so confused :frown:

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It's nitrile to carboxylic acid ...

... what is used to do that?

Reply 2

whatacrydonnie

Original post by 3mma_gal96

The q asks for the reagents and conditions required, plus the name of the reaction needed for step 5, so to convert compound D to ibuprofen.

I'm so confused :frown:

Posted from TSR Mobile

"Acidic hydrolysis of nitriles

The nitrile is heated under reflux with dilute hydrochloric acid. Instead of getting an ammonium salt as you would do if the reaction only involved water, you produce the free carboxylic acid.

For example, with ethanenitrile and hydrochloric acid you would get ethanoic acid and ammonium chloride.

Why is the free acid formed rather than the ammonium salt? The ethanoate ions in the ammonium ethanoate react with hydrogen ions from the hydrochloric acid to produce ethanoic acid. Ethanoic acid is only a weak acid and so once it has got the hydrogen ion, it tends to hang on to it."

From chemguide.co.uk

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Reply 3

3mma_gal96

Thankyou so much guys! Nitriles were covered when I was absent so that makes sense why I didn't get it, but that helps a lot, thanks!

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