CO2

[Alysson Marines 2E]

Why is it an electrophile?

[Esther Qiu 2B]

It's because of it's oxidation state (4).

[Jiangyuan Luo 1K]

A easy to way to think about it. CO2 can react with OH-, which is obviously a nucleophile, so CO2 must be a electrophile.

[KelseyKobayashi_2M]

Are we always supposed to just look at the charge of the central atom to determine whether is it an electrophile or nucleophile?

[Kayla_Black_2B]

^ I don't think so, just because sometimes electrophiles and nucleophiles can be neutral (it's just more rare). For example, on pg.81 of the course reader, AlCl3 is listed as an electrophile. More of this is discussed in section 4.1 of the organic textbook.

However, I am also surprised C02 is an electrophile...I figured all of the lone pairs on the O atoms would make it a nucleophile...

[Wendy_Liu_3A]

If you look at the lewis structure of CO2, you find that C is the central atom with O on either side. Each oxygen has 2 lone pair electrons, making the charge of oxygen partially negative. Since the oxygen is partially negative, C is partially positive. To determine whether a molecule is electrophile or nucleophile, we only look at the molecule's central atom, which is C in this case. Since C is partially positive, it is attracted to negative, or electrons. C's affinity for electrons makes CO2 an electrophile .