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finding an ester (chemistry)

does anyone know what the ester reaction of 2-bromo-5-hydroxy-benzoic acid + hexanoic anhydride is?
Original post by Lana123456789
does anyone know what the ester reaction of 2-bromo-5-hydroxy-benzoic acid + hexanoic anhydride is?


Start by drawing out the structures of both compounds, if you can.

Is there an alcohol group on the hexanoic anhydride?
Original post by TypicalNerd
Start by drawing out the structures of both compounds, if you can.

Is there an alcohol group on the hexanoic anhydride?

Yeah there is an alcohol group present
Original post by Lana123456789
Yeah there is an alcohol group present

Are you sure? Have you attempted to draw out the structures of the reactants?

Hint: acid anhydrides contain the O=C-O-C=O group.
Original post by TypicalNerd
Are you sure? Have you attempted to draw out the structures of the reactants?

Hint: acid anhydrides contain the O=C-O-C=O group.

Ah okay so then is it the carbonyl group instead of the hydroxyl group
Original post by Lana123456789
Ah okay so then is it the carbonyl group instead of the hydroxyl group

Hexanoic anhydride indeed does have carbonyls and no hydroxy group, but supposing you were to break off a -O-CO(CH2)4CH3 chain from it, what would it leave behind?
Original post by TypicalNerd
Hexanoic anhydride indeed does have carbonyls and no hydroxy group, but supposing you were to break off a -O-CO(CH2)4CH3 chain from it, what would it leave behind?

Honestly, I’m not sure but the acid anhydride group?
Original post by Lana123456789
Honestly, I’m not sure but the acid anhydride group?


Ok, let’s use another approach.

Hexanoic anhydride is the acid anhydride of hexanoic acid, so during the reaction, it serves as the source of the carboxylic acid part of the ester. What does that tell you about part of the structure of the ester?
Original post by TypicalNerd
Ok, let’s use another approach.

Hexanoic anhydride is the acid anhydride of hexanoic acid, so during the reaction, it serves as the source of the carboxylic acid part of the ester. What does that tell you about part of the structure of the ester?


didn’t wanna leave you hanging but something popped up and I don’t think I’ll be needing the answer any longer but I honestly appreciate the help. Thank you so much.
Original post by Lana123456789
didn’t wanna leave you hanging but something popped up and I don’t think I’ll be needing the answer any longer but I honestly appreciate the help. Thank you so much.


Fair enough.

Hopefully you now understand how to work out the products of esterification reactions given a pair of reactants (which is what I was attempting to guide you through, hence why I didn’t just give a straight answer).

You are welcome. Feel free to ask further questions if needed.

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