00:02
Hello everyone, let's look at the question.
00:04
So here three questions are given and also we have to answer this one by one.
00:08
First, let us take the first question.
00:11
So here it is said that the chlorobenzin is less reactive towards electrophilic aromatic substitution than benzene, but incoming substituents are directed into auto and para position.
00:21
Now if we consider chloropensin and benzene, so the chlorobenzion is less reactive towards electrophilic substitution reaction compared to benzene.
00:35
So the reason is because the.
00:37
Because the.
00:37
Chlorine is exhibiting minus i effect due to it so it withdraws the electron from the benzeneering so that the electron density of the the benzeneering decreases okay so that's why it is less reactive towards electrophilic substitution reaction okay because in case of electrophic substitution reaction so here electrophile will substitute the another electrophile okay now so here for that that this benzene ring, it should be nucleophilic for the electrophile to attack here.
01:13
That if this benzoning itself is the less electron density, itself is having less electron density.
01:21
Then the electrophile attack of electrophile to the benzene ring, they will seize.
01:27
That's why, so the reactivity also ceases.
01:29
Now here, so it is already said that the chlorobenzion is, so less reactive towards electrophilic substitution, but still it directs the incoming electrophile towards ortho and paraposition.
01:42
So here, along with minus high effect, it also has the plus r effect or plus m effect, that is a resonance or mesomeric effect.
01:51
So, because of that the mesomeric effect, so the ortho and paraposition will be more electron rich.
02:00
Okay, that's why the incoming electrophile will attack it, ortho and para position.
02:05
Okay.
02:06
Now here we can see that.
02:08
So the chlorobenzene is less reactive towards electrophilic substitution reaction than benzene because of negative inductive effect or minus i effect exhibited by chlorine on benzene ring which decreases electron density of benzene.
03:37
But since chlorine also exhibits plus m effect or plus r effect, ortho and para position are more susceptible electrophilic attack.
04:21
So they are more susceptible for electrophilic attack.
04:36
So that's why even though it is less reactive, so it is orthopara direct.
04:44
Because it also exhibits plus an effect.
04:47
Okay.
04:48
Now here let us move on to the second one.
04:51
Now in the second question, so it is asked that nitration of aniline gives only small amount of metanitro anilin as the only organic compound.
05:02
Okay, now here if we take nitration of anilin, so here, so it will give you a mixture of products.
05:18
So here it is done in the presence of nitrating mixture, concentrated, hno3 and constitute h -desopore.
05:30
So here the major product is para product, that is para -nitro -anilin.
05:39
And then the next major product is metanitro -anilin.
05:48
So then comes orthonitroniline.
05:58
So here about 51 % will be of para.
06:03
So 47 % will be of meta and only about 2 % will be of para.
06:09
Or two.
06:10
Now here why this happens because see we know that an h2 group is electron donating group it's the product should have been orthoine para okay the but the the meta nitrogonylin is formed as the major product instead of ortho so this is now here the para is formed because aniline is in case of an nitrogen group is or nitrogen atom is donating its electron to the benzene ring so that ortho and para positions are around it so that anoto group can easily attack.
06:42
Now in case of orthoposition what happens there is a steric hindrance because of which attack of nitro group will be hindered.
06:52
Now in case of metaposition so here what happens that so in case of anilin so since it is carried out in an acidic condition so some of the anilin so they get converted into in the presence of acid ammonium ion.
07:11
That is nh3 plus when this forms an h3 plus so there will be no mesomeric effect the at means there will be more positive mesomeric effect so here it is exhibiting minus i effect okay so since it is exhibiting minus i effect so the ortho and para positions are no more electron rich okay so here now the metaposition becomes electron rich compared to other positions okay now here nitrogen will abstract the electron density from the benzate that's why compared to ortho and para now metaposition becomes electron rich that's why nitrogrop will attack okay so that's why when you do the nitration of anilin so here significant amount of meta nitroalin is also formed okay so in along with para and ortho so here so here actually not a small amount of metanitroniline is not formed so here metanitroniline is formed in a significant amount...