It's worth noting that nitro groups or nitrobenzene is often used as a precursor to get to aniline. Remember that aniline is an amino group on a benzene ring. That's called an aniline molecule. Nitro groups can be easily reduced to aniline. As you can see, a reduction reaction chapter, I do want to go through it right now and just kind of clue you guys in to some of the most important reducing agents that can make this conversion happen. Now the one we always want to start with and probably want to be our default whenever we think reduction is lithium aluminum hydride. That's just because this is the most common reducing agent of all of organic chemistry. It's also one of the strongest. Lithium aluminum hydride will absolutely get the job done and will absolutely turn a nitro group into aniline. But there are a few other types of reagents that can do the same thing that you also might see. So does it recognize H2 and a palladium catalyst? This also goes for a nickel or a platinum catalyst. These would be the reagents used in catalytic hydrogenation. I'm just going to put here these are the reagents for catalytic hydrogenation and that will definitely reduce your nitro group to an aniline. Now one that's actually really special kind of important here is Tin chloride in water or it's also known as stannous chloride. This benzene is just going to have to get written on because I don't have that much room. Stannous Chloride. This one is particularly special here because we're going to talk a little bit more about this later. This is actually your only chemoselective reducing agent. What does that mean? What it means is that by saying that it's chemoselective, what I'm saying is that it has a tendency to only reduce nitrile groups and nothing else. It's like kinda talented at doing that And it really doesn't like to reduce many other types of groups. So that's gonna be important when we have other groups that are vulnerable to reduction. Stannous chloride is a great choice because it really just hones in on the nitrile groups and turns them into aniline. Finally, really common reducing agents are either iron or zinc in the presence of HCl. You'll see this all the time. These reagents turn into strong reducing agents that will reduce a nitro group into aniline. Really, the exact reducing agent that you're going to wind up using the most is going to probably be up to your professor more than anything else. But keep in mind, bear in mind that all these reagents could be used in some way or another to reduce a nitro group to an aniline. My personal favorite is going to be the Tin II Chloride, the stannous chloride. That's the one that I'm going to use the most often in this course because I know that it's chemoselective specifically for the nitro group, so it has very high yields of aniline when we use it. Okay. So let's move on to the next topic.
19. Reactions of Aromatics: EAS and Beyond
EAS:Nitration Mechanism
19. Reactions of Aromatics: EAS and Beyond
EAS:Nitration Mechanism - Online Tutor, Practice Problems & Exam Prep
EAS Nitration requires nitric acid to react with a catalytic acid to generate a strong nitronium ion electrophile.
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EAS Nitration
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Reduction of Nitro Groups
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Video transcript
A ntiro group can be reduced to aniline with many reducing agents, as we see below:
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PRACTICE PROBLEMS AND ACTIVITIES (10)
- Propose a mechanism for nitration of pyridine at the 4-position,and show why this orientation is not observed.
- Before spectroscopy was invented, Körner’s absolute methodwas used to determine whether a disubstitutedbenzene...
- Before spectroscopy was invented, Körner’s absolute methodwas used to determine whether a disubstitutedbenzene...
- Before spectroscopy was invented, Körner’s absolute methodwas used to determine whether a disubstitutedbenzene...
- Give the structures of compounds A through B in the following series of reactions.<IMAGE>
- Predict the major products formed when benzene reacts (just once) with the following reagents.(j) nitric acid ...
- Biphenyl is two benzene rings joined by a single bond. The site of substitution for a biphenyl is determined b...
- Biphenyl is two benzene rings joined by a single bond. The site of substitution for a biphenyl is determined b...
- (a) Draw the three isomers of benzenedicarboxylic acid. (b) The isomers have melting points of 210 °C, 343 °C...
- What product(s) result from nitration of each of the following?e. benzenesulfonic acid f. cyclohexylbenzene