Organolithium

[sugarbabee0]

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RX + 2 Li → RLi + LiX

How are both Li's oxidized? The way I'm thinking of it is that R is + and X is -.
So the products would be R+Li- and Li+X- (therefore one Li oxidized and one reduced. What am I doing wrong?

 

[Rabolisk]

R is negative, not positive. The point of organilithium agents is that they are excellent nucleophiles, due to the negatively charged carbon. R-Li+

Lithium would NEVER have a negative charge on it.

 

[orgohacks]

RX + 2 Li → RLi + LiX

How are both Li's oxidized? The way I'm thinking of it is that R is + and X is -.
So the products would be R+Li- and Li+X- (therefore one Li oxidized and one reduced. What am I doing wrong?

Lithium pumps electrons into the R-X bond, one at a time.

Exactly like the Grignard reaction, except Mg has two electrons so you only need one equivalent of Mg. To make the organolithium you need two electrons, hence two equivalents of Li.

Rabolisk is right, Li would never have a negative charge on it.

If you're extremely curious the first reaction makes something like R• + LiX, which is quickly reduced by a second Li to give R(-)Li(+). But you definitely don't need to know that.