Now we're going to talk about a specific reaction called a Hofmann elimination. The name Hofmann elimination can be a little confusing because we've used both of these terms before. We've talked plenty about elimination reactions in Organic Chemistry 1 and we learned that they could either follow Zaitsev's rule or Hofmann's rule. But when I mention Hofmann elimination here, I'm not referring to that. I'm referring to a specific reaction called Hofmann elimination, not Hofmann's rule regarding elimination. This is also referred to as exhaustive methylation or Hofmann degradation. If you hear any of those words or if your professors call it any of those other terms, just know that this is the same reaction. The name Hofmann elimination actually is helpful for us because it's going to serve to remind us that we're going to produce a Hofmann elimination product, meaning that it is going to follow Hofmann's rule but specifically it's going to be within an amine. In Organic Chemistry 1, we learned that alcohols can be eliminated, dehydrated to form double bonds. That was actually a reaction called dehydration. In the same way, amines can too. But they need to be turned into a good leaving group because amines as they are, if you were to kick off an NH2-, it's a terrible leaving group. That's like the strongest base ever. The point of the first step of this reaction is going to be to try to make the nitrogen a good leaving group, so then we can kick it out and do an elimination reaction with a base. That's exactly what the first step is. The first step is going to be some kind of alkyl halide, usually an alkyl iodide. You may see it written as in excess or you may not. In the absence of data telling you excess or a number of equivalents, always assume that there's excess. In this case, I don't have to write excess but your professor may be nice and write excess. Now what that's going to do is it's g
26. Amines
Hofmann Elimination
26. Amines
Hofmann Elimination - Online Tutor, Practice Problems & Exam Prep
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General Reaction
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PRACTICE PROBLEMS AND ACTIVITIES (11)
- The following reaction takes place several times faster than the reaction of 2-chlorobutane with HO-: b. Exp...
- Describe a synthesis for each of the following compounds, using the given starting material and any necessary ...
- What are the minor products of the preceding Hofmann elimination reaction?
- What are the major products of the following reaction?
- What is the major product of each of the following reactions? b.
- The following reaction takes place several times faster than the reaction of 2-chlorobutane with HO-: a. Exp...
- Using any necessary reagents, show how you would accomplish the following syntheses. (c) < of reaction>
- Predict the products of the following reactions: (j) < of reaction>
- Predict the products of the following reactions:(e) <IMAGE of reaction>(f) <IMAGE of reaction>
- Predict the major products formed when the following amines undergo exhaustive methylation, treatment with Ag...
- When the (R,R) isomer of the amine shown is treated with an excess of methyl iodide, then silver oxide, then h...