LAH is the more powerful reducing agent than sodium borohydride due to the weaker Al-H bond compared to the B-H bond.
And why's that? I don't remember for sure.
I would guess because B-H has less electronegativity difference, so makes a more covalent-ish bond than Al-H, which would be more ionic.
Possibly totally wrong, but if it's wrong, I'm fine with you telling your professor, "I got my answer from a total stranger on the internet, so I didn't come up with this crap. It's his fault."
· 1 decade ago