Why are weak lewis bases strong nucleophiles?

1 Answer
Sep 3, 2014

Electrophiles are Lewis bases because the two definitions have the same definition in terms of electrons.

In the Lewis definitions of acids and bases, a Lewis acid is defined as an electron pair 'acceptor', which will acquire an electron pair. A Lewis base is anything that gives this electron pair, hence the term 'donor'.

A nucleophile is a chemical species that donates an electron pair to an electrophile to form a chemical bond in relation to a reaction. (https://en.wikipedia.org/wiki/Nucleophile) In other words, a nucleophile is an 'electron loving' chemical.

You can see that the two definitions overlap in terms of giving electrons. A nucleophile will give electron pairs, and thus by definition are Lewis bases, and vise versa.