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Organic Chemistry

Learn the toughest concepts covered in Organic Chemistry with step-by-step video tutorials and practice problems by world-class tutors.

21. Enolate Chemistry:Reactions at the Alpha-Carbon

Base-Catalyzed Alpha-Halogentation

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Base Catalyzed

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Now, this is in contrast to the base catalyzed mechanism. Okay, so in the base catalyzed mechanism, you may yield Paulie hallucination. Okay. And the reason is, you basically gonna yield as much holiday nation as you have Alfa protons. The reason being, guys, that in a base catalyzed mechanism, the X is being there is just gonna make it more reactive. The second time, let me show you. So in a base catalyzed mechanism, imagine that I'm using O h negative and that I'm just forming an equally right away. And that email it looks like this negative charge. Okay, well, that negative charge can react with x two to this to that. Go here, Go there and give me my halogen. Okay. But now, when it sees that second equivalent of base, because what's gonna happen now, we have a die poll pulling away. So it's gonna be easier to put a negative charge there because the negative charge is gonna be stabilized by the halogen. Therefore, we're going to replace every single halogen that was for every single hydrogen that was there. We replaced all of those alfa hydrogen with exes, and we're gonna get Paulie substitution Okay. Now, the only reason that I put may yield not will yield is because obviously you need multiple Alfa protons in order for it to get Polly College needed. Okay, If you only have one, then you're only gonna substitute once. But you can basically continue to react. Continue to keep reacting until you're out of Alfa Protons. Interesting, right? Cool guys. So in the next video, I want to show you an application of Alcoholic Nation called the Hala form reaction.
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Problem

Provide the major product for the following reaction. 

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