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Organic chemistry reaction

How will this react with h3po4? I haven't seen this before.
Original post by Illumilottie
How will this react with h3po4? I haven't seen this before.

Dehydration forming an alkene.
Original post by charco
Dehydration forming an alkene.


Isn't hydration using h3po4
Original post by Illumilottie
Isn't hydration using h3po4


Yeah but you need steam as well
Original post by Illumilottie
How will this react with h3po4? I haven't seen this before.


just ignore the carboxyl group so it would be an alcohol to alkene
Original post by Illumilottie
How will this react with h3po4? I haven't seen this before.

H3PO4 acts as an acid catalyst.
https://www.chemguide.co.uk/organicprops/alcohols/dehydration.html for more info :smile:

Original post by Illumilottie
Isn't hydration using h3po4

Dehydration = loss of water (or another small molecule)
Basically the acid protonates the -OH, forming -OH2+ , and then H2O is lost from the main molecule. As well as this, a hydrogen on an adjacent carbon is lost and the double bond is formed.
Since the starting molecule is a secondary alcohol, this happens in 2 steps (E1).
https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Map%3A_Organic_Chemistry_(Wade)_Complete_and_Semesters_I_and_II/Map%3A_Organic_Chemistry_(Wade)/14%3A_Reactions_of_Alcohols/14.04%3A_Dehydration_Reactions_of_Alcohols has a nice diagram :smile:

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