All right. So I know that I already told you guys that this was an e one reaction, but how would you know that if I wouldn't have told you? Okay? Now just so you know, this entire question of what mechanism do I use is going to be the very last topic that we end on for this lesson. And I'm going to spend a lot of time explaining how to determine that. But even before we have all the tools, we can already start to just use our logic of knowing nucleophiles and leaving groups to figure this out. So what I would say is, okay, what type of nucleophile do I have? Is it strong or is it weak? Well, in this case, m e o e h stands for methanol. This would just be CH3OH. Is that negatively charged or neutral? That's neutral. Okay? And if that's neutral, that means that it's weak. Okay? So that means that is it going to start off by doing a backside attack or an e2 elimination? No. It's just going to chill. It's just going to stay there for a while. What type of leaving group do I have? Okay. I have a tertiary. Okay. What is tertiary really good at doing? Making carbocations. So I know that my first step is going to be to make a carbocation and that means that my mechanism is going to be a combination of E1 and SN1. Is that cool? Awesome. So let's go ahead and draw this mechanism. The first part of the mechanism is going to be the same for both for all the products. It's just going to be that my f leaves on its own. Okay? What What that's going to do is it's going to give me a carbocation that looks like this. Okay? And that was my right here, this is my rate That's my rate determining step. Okay? Now, what happens after this is what determines which path I take. Okay? If my methanol pulls off a beta proton, that is going to be an elimination. So how many different types of beta protons do I have? That's my alpha. By the way, my alpha is now whatever has the carbocation. Well, I have 3 betas. Beta, beta, beta. Do all of them have at least 1 hydrogen on them? Yes. Do all of them are they all the same? Are they different? They're all the same. So it doesn't matter which one I pick. I'm just going to pick this one over here for my H. Remember that also anticoplanar doesn't matter because it is E1. I'm going to take my CH3OH and I'm going to pull off that proton. So what I'm going to get for the e one mechanism is that and that e one. And what I'm going to wind up getting is a double bond that looks like this. Is that cool? So that's my elimination product and that would have been that's my only product. But remember that I could have gotten a mixture of products if I would have had more than one type of beta hydrogen. Cool? So that's the e one. So we're done with that. But like I said, every time you get an e one, now you're going to have to be thinking about SN1 as well. So let's just go ahead and draw that really quick. So remember that for sn1 and this is also good practice of the sn1 mechanism. So remember that for sn1, what I would do is I would take my c h three o h and I would directly attack the carbocation. What that's going to give me is a new compound that looks like this where I have the 3 methyl groups and now that's attached to o with an H in one place and with a CH3 in another and a positive charge. Okay? So remember that Sn1 was a little bit annoying because remember that Sn1 always requires a proton removal step or what we just called deprotonation. Okay? This is the only mechanism that requires a deprotonation because you always get a formal charge at the end. So do you guys remember what I could use to take away that h? I could just use another I could use the thing that left, which should just be my f negative. So I have my f negative and I'm going to pull it off. F to h and then these electrons down to o. Now I have to ask myself, did I make a new chiral center? Are there any chiral centers on that molecule, on the SN1? Right here. No. It's not chiral. So I'm only going to get one product and it would just look like this. O c h three. Okay? So that was my this part was my s n one. It's hard to know where to put it. I guess I'll just put it here. This one was my SN1 where I attacked directly. The red one was my e1 where I did a beta elimination. And in the end, I wound up with 2 different products. Now, this is honestly one of your best case scenarios for e1 or sn1 where you just get one product for each. But like I said, sometimes you can get up to 5 products. The reason 5 is because you could have 3 different double bonds because you have 3 different types of eliminations. Then you could get 2 enantiomers for the SMO one. And that's just crazy. So I'm not going to make you draw all 5, but we are going to draw now question b and question b is going to have more products than the one that I just drew. So go ahead and try to get all of the products for b using both mechanisms and also the logic of why were you going to use these mechanisms. So go for it.

Table of contents

1. A Review of General Chemistry5h 5m
2. Molecular Representations1h 14m
3. Acids and Bases2h 46m
4. Alkanes and Cycloalkanes4h 17m
5. Chirality3h 39m
6. Thermodynamics and Kinetics1h 22m
7. Substitution Reactions1h 48m
8. Elimination Reactions2h 30m
9. Alkenes and Alkynes2h 9m
10. Addition Reactions3h 19m
11. Radical Reactions1h 58m
12. Alcohols, Ethers, Epoxides and Thiols2h 42m
13. Alcohols and Carbonyl Compounds2h 17m
14. Synthetic Techniques1h 26m
15. Analytical Techniques:IR, NMR, Mass Spect7h 3m
16. Conjugated Systems6h 13m
17. Ultraviolet Spectroscopy51m
18. Aromaticity2h 34m
19. Reactions of Aromatics: EAS and Beyond5h 1m
20. Phenols55m
21. Aldehydes and Ketones: Nucleophilic Addition4h 56m
22. Carboxylic Acid Derivatives: NAS2h 51m
23. The Chemistry of Thioesters, Phophate Ester and Phosphate Anhydrides1h 10m
24. Enolate Chemistry: Reactions at the Alpha-Carbon1h 53m
25. Condensation Chemistry2h 9m
26. Amines1h 43m
27. Heterocycles2h 0m
28. Carbohydrates5h 53m
29. Amino Acids4h 20m
30. Peptides and Proteins2h 42m
31. Catalysis in Organic Reactions1h 30m
32. Lipids 2h 50m
33. The Organic Chemistry of Metabolic Pathways2h 52m
34. Nucleic Acids1h 32m
35. Transition Metals6h 14m
36. Synthetic Polymers1h 49m

8. Elimination Reactions

E1 Reaction

Organic Chemistry

8. Elimination Reactions

E1 Reaction

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Multiple Choice

Predict the product

E1 reaction diagram with hydroxyl group and product prediction.

E1 reaction diagram with hydrogen and product prediction.

E1 reaction diagram with methoxy group and product prediction.

E1 reaction diagram with no substituents and product prediction.

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Verified step by step guidance

Identify the starting material as a tertiary alkyl fluoride. The carbon attached to the fluorine is a tertiary carbon, which is prone to undergo substitution reactions.

Recognize that methanol (MeOH) is a polar protic solvent, which can facilitate a nucleophilic substitution reaction, particularly an SN1 mechanism.

In an SN1 reaction, the first step is the formation of a carbocation intermediate. The C-F bond breaks, resulting in the loss of the fluoride ion and the formation of a tertiary carbocation.

Once the carbocation is formed, methanol can act as a nucleophile and attack the positively charged carbon, forming a new C-O bond.

Finally, a proton transfer occurs where the methanol group loses a hydrogen ion, resulting in the formation of an ether product with a methoxy group replacing the fluorine atom.