Why is N- a better nucleophile than S-?

Question

I can't rationalize why S- is a worse nucleophile than N-. I thought nucelophilicity was related to electronegativity, the more electronegative an atom is, the less of a nucleophile it is. Sulfur is less electronegative than Nitrogen. What concept am I not considering or misunderstanding?

Well, if that was so simple... In organic chemistry thinking in terms of electronegativity is hardly enough to guess even acidity. — Mithoron, Dec 03 '19 at 21:20

score 2 · Accepted Answer · answered Dec 03 '19 at 18:03

2

I think it would be nice to consider the charge density. The S- is more stable than N- because it has more electron shells, so the negative charge density is better distributed in the atom. It makes that the N- is more likely to give up electrons and act as a nucleophile

answered Dec 03 '19 at 18:03

Arnau

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4

Why wouldn't that apply to oxygen versus sulphur? – ReftPowered Dec 03 '19 at 18:44
I would swear that the carboxylate can stabilize by resonance and thiolate not – Arnau Dec 03 '19 at 19:08

Why is N- a better nucleophile than S-?

1 Answers1