The Retro Claisen Condensation

[@juliahtunnaung3931]

You're a hidden gem! Sent your channel to all my friends taking ochem rn

[@jOeCHEM]

Julia, thank you SO much, for both watching and recommending 🤓

[@juliahtunnaung3931]

Thank you so much!!! That aha moment was soooo satisfying for me

[@Moth-tr1gq]

Great explanation! Great Video !

[@Will-le4lm]

Hey man, thanks for making this video, it was pretty helpful.

[@Maxchem]

thank you so much!!! Your video helps me a lot

[@Shirl33n]

Thank you this was very helpful, definitely had that aha moment

[@juliam5549]

Very helpful thank you!

[@chestar3717]

thank you for this, I'm so grateful i came across your channel! I have a question, at 10:31 why did the oxygen kick out the OMe group not the other group?

[@salomeschliomkis7839]

Hi!, not Joe and also really late, but I think it's because de MeO- is a better leaving group than the enolate. If you check the pKa's, the enolate of the esther (pKa 25 aprox) is a stronger base than the methoxide (pKa 16 aprox), so the latter is a best leaving group. The leave of a methoxide also allows the reaction to form the beta keto esther which have much more acidic alfa protons that the metoxide, so this base can abstract one alfa proton and form the enolate highly stabilized by resonance, which displaces the equilibrium to the products. If the enolate leaves instead, we form an esther and a enolate of an esther. An enolate of an esther is least stabilized by resonance than the enolate of the beta keto esther, so the pathway where the enolate is the leaving group isn't favoured in this case. In the retro-claisen the enolate is the leaving group because in this case we do not form the beta keto esther if the methoxide leaves. As Joe said, it is key that the beta keto esther substrate doesn't have alpha hidrogens, this way the methoxide can't deprotonate it and form an enolate highly stabilized by resonance. If this had happened, then it would be very unlikely the nucleophilic attack by the methoxide on the carbonyl carbon. Hope this helps honestly, sorry for the long paragraph, I tried to explain it the best I could.

[@chrisnguyen1]

Great video. Thanks!

[@aaryan__bondekar9778]

Noice video and channel, useful for jee advanced

[@bn3041]

Thank you a lot

[@jOeCHEM]

Thank YOU for watching. Make sure to check out joechem.io (my website) where all the videos are listed + guided worksheets with solution (all for free!). Also, I'm still working on finishing the back half of OChem II. And if you'd subscribe to my channel, I'd massively appreciate it!