So, I know alkane is not soluble in water, but it is a base. So, when does it react with water as a base?
When does alkane react with water?
- Thread starter DingDongD
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Water is not acidic enough to donate a proton to the pi bond in an alkene or alkyne.
The reaction requires a catalytic amount of acid to protonate the pi bond and form a carbocation intermediate. Water is nucleophilic enough to attack the carbocation and form an alcohol product. This will not occur without an acid catalyst though.
The reaction requires a catalytic amount of acid to protonate the pi bond and form a carbocation intermediate. Water is nucleophilic enough to attack the carbocation and form an alcohol product. This will not occur without an acid catalyst though.
This question just came to me, can a primary, secondary or tertiary carbocation ever participate as a acid base reaction with water as a base? Would it just be the case with alkenes and alkynes regarding to the pi orbitals? I know water can be a nucleophile.
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Yes, the carbocation is a strong Lewis acid due to being highly electron deficient and bearing a formal positive charge - this is the second step of the reaction I described in my previous post. Water acts as a Lewis base due to the lone pair of electrons.
If you are asking if water will act as a Bronsted-Lowry base with a carbocation - that is not a reaction I have heard of. I guess theoretically it could be done, but most mechanisms simply proceed with nucleophilic attack by water.
I don't know what "Would it just be the case with alkenes and alkynes regarding to the pi orbitals?" means.
If you are asking if water will act as a Bronsted-Lowry base with a carbocation - that is not a reaction I have heard of. I guess theoretically it could be done, but most mechanisms simply proceed with nucleophilic attack by water.
I don't know what "Would it just be the case with alkenes and alkynes regarding to the pi orbitals?" means.
Nope, that explains it. I was thinking it might be linked to pi orbitals since a carbon cation has one and water might not be acidic enough. Thank you for your time! Really appreciate the answers.
