Concept: Concept: Ammonia Derivatives3m
In this video, we’re going to discuss all the different things that you can make when you react an ammonia derivative with a carbonyl.
At this point you should feel pretty comfortable with the reaction of ammonia with a carbonyl. We know that in the acidic environment, you add ammonia to a carbonyl and you're going to get it an imine, nitrogen double bond carbon. Looks like a carbonyl except it’s a nitrogen. What would happen if instead of reacting with NH3, you take out one of the Hs, so NH2 and you replace it with something else. Let's say you replace it with another amine. Then what would happen? This is where you get your imine derivatives. Ammonia derivatives are going to yield what we can call in general imine derivatives.
Because your imine derivatives all look exactly like imine except that they just have different functional groups coming off of the nitrogen. I would commit these to memory if I were you because they're functional groups you should know and you never know if your professor mixes it up and instead of giving you a normal amine gives you hydrazine.
Then what would happen? Hydrazine is the name of NH2 with another any NH2. When hydrazine reacts with a carbonyl in an acidic environment, it makes hydrazine. Damn, that's confusing. Hydrazine goes to hydrazone. It makes sense. The names are super similar but make sure that you don't mix up the two. One easy way to think about it is that hydrazine and ketone make hydrazone. Hydrazine would be the mixture of both. What if you reacted with an NH2 and an OH? That’s called a hydroxylamine and that's going to give you functional group called an oxime. An oxime would be an imine with an OH coming off of the top. Finally, if you were to take a hydrazine but put a phenol on it, that's a phenylhydrazine. Phenylhydrazine is going to yield phenylhydrazone when you react it with ketone.
These are all different combinations that all follow the exact same mechanism as an imine addition except that they're just derivatives of an amine that reacts to make a derivative of the imine as a product. Now, I’m giving you a problem down here. Go ahead and see what you get. See if you can figure out how to react this big molecule with ketone and then I'll show you the answer.
Concept: Example: Brady's Reagent3m
So there was a lot going on on that benzene molecule but there was only one part of it that could react with the ketone and that was the hydrazine so this is just a derivative of hydrazine. In fact this molecule is actually it's called 2, 4 DNP and it's actually used as Brady's test so this is a molecule that you might actually use in a chemistry lab this semester because it's a very famous test to test for ketones. What happens is that when you make the phenylhydrazone product that phenylhydrazone will precipitate out of the solution and it usually precipitates like a yellow, orange or red colour.
If you get that precipitate you have a ketone present. So this is actually a test that's used to detect ketones. Let's see what the phenylhydrazone product would look like. Well we know that I mean obviously I'm not going to draw the whole mechanism because that's not what this question asking, just asking to predict the product, so I would go ahead and I would draw me emine but I need to attach the hydrazone part in fact it's going to be a phenylhydrazone. So I'm going to add N H, let's see what else is attached to it well we've got a benzene ring and that benzene ring has 2 nitrile groups so let's add those, N O 2, N O 2 and that would be it, that's our molecule.
So this is basically a phenylhydrazone, right? Phenylhydrazone and in fact it's a 2,4-dinitrophenylhydrazone because this is the 2,4-dinitro part. 2 and 4. So do you think you can figure out where the name comes from? It's 2,4-dinitrophenylhydrazone so that's why it's called 2, 4 DNP. It's a great example of an emine derivative and it's actually a reaction that you might see later this semester so if it comes up, you'll say hey I learned that clutch. Maybe you can tell your lab partner so that they'll know about clutch too and more people would know about us. Awesome, alright so let's move on to the next topic.
Show what amines and carbonyl compounds combine to give the following derivatives.
Predict the products of the following reactions.
2,4-Dinitrophenylhydrazine is frequently used for making derivatives of ketones and aldehydes because the products (2,4-dinitrophenylhydrazones, called 2,4-DNP derivatives) are even more likely than the phenylhydrazones to be solids with sharp melting points. Propose a mechanism for the reaction of acetone with 2,4-dinitrophenylhydrazine in a mildly acidic solution.
Complete the following reaction by drawing the structure of the principal major product. Indicate relative stereochemistry where necessary. If there is no reaction, write NR.
Give a stepwise mechanism that accounts for the following transformation:
From the options below, choose which number is the reagent that will convert unknown product A into our final product. Then draw the structure for compound A.
Please provide a detailed arrow pushing mechanism for the following transformations.
Complete the following reaction by drawing the product in the box. If the reaction will not proceed as written, write NR in the box.
Determine the correct answer for the question below.
Draw the structural formula, including stereochemistry when necessary, of the organic product(s) for the following reaction.
What product results from treating butanal with H 2N-OH in mild acid?
d) Butanoic acid
e) None of the above