00:01
Hello students, in this question we have been given a reaction in which there is a diol.
00:07
Diol is basically a molecule containing two hydroxyl groups like this.
00:13
We have to treat it with acetone in presence of an acid.
00:19
So, let's start the mechanism.
00:21
In the first step this acetone carbonyl group will be protonated with the help of this acid.
00:30
So, oxygen contains the lone pairs.
00:32
This will attack on this hydrogen as a result of which these electrons will move towards oxygen.
00:42
Now this will be the electron flow.
00:45
Hence this carbon will get a positive charge and a oh bond will be formed.
00:51
Now in this attack electrons are donated to h plus ion.
00:58
So, we can say that in this step h plus has acted as an electrophile and the species that has extra lone pairs to attack is known as nucleophile.
01:16
So, oxygen atom with lone pairs has behaved as a nucleophile.
01:25
Now let's proceed with the second step of mechanism.
01:29
In the second step our diol will attack on this carbonyl.
01:39
This contained a positive charge and there were electrons on both the oxygen atoms.
01:47
So, these will attack here.
01:51
Hence we will get one of the hydroxyl group bonded to our acetone.
02:02
This will become oh and this oxygen will now get a positive charge.
02:09
In this reaction this oxygen is acting as a nucleophile and this carbonyl with a positive charge that is carbon atom is acting as an electrophile.
02:23
Now let's proceed with the next step.
02:27
Next step will involve deprotonation...