00:01
Label the lewis acid and the lewis base in each pair and add curved arrow notation, otherwise known as a mechanism to get from the starting materials to the products.
00:10
So for this first compound, we start with cl minus and bcl3 in order to form bcl4 minus, and this comes from forming a new bond between chlorine and boron.
00:23
So we can draw the lone pairs on chlorine attacking boron.
00:29
That gives boron a formal negative charge, but it also gives boron a phallocet.
00:36
So in this case, chloride is acting as a base.
00:41
Boron is acting as a lewis acid, meaning it's accepting a lone pair of electrons in order to get to this species.
00:48
In this next case, we lose a double bond to get to a single bond, and we have a positive charge on this carbon.
00:55
So what's happening here is the pie bond is acting as the base in order to attack a hydrogen.
01:05
If you attack that hydrogen, you can't have two bonds to it, so you have to break the oxygen -hydrogen bond in order to get to here.
01:12
The other byproduct is going to be the anion of sulfuric acid, and this is stabilized through resonance.
01:27
That might be something you want to draw...