Question

Is an aldehyde polar? What occurs when it reacts with methyl magnesium chloride?

Answer 1

The carbonyl bond is polar in that there is charge separation.

Explanation:

Oxygen is more electronegative than carbon, and polarizes electron density towards itself. A representation of the carbonyl bond as `-""^(delta+)C=O""^(delta-)` is reasonable, and this certainly accounts for the reactivity in say a Grignard reaction, i.e:

`R^(-)""^(+)MgX + R'C(=O)H rarr R'RC(-O^-)(MgX)^+`, in which a carbanionic reagent reacts with the carbonyl to effect `C-C` bond formation.

Answer 2

The carbonyl bond is polar in that there is charge separation.

Explanation:

Oxygen is more electronegative than carbon, and polarizes electron density towards itself. A representation of the carbonyl bond as `-""^(delta+)C=O""^(delta-)` is reasonable, and this certainly accounts for the reactivity in say a Grignard reaction, i.e:

`R^(-)""^(+)MgX + R'C(=O)H rarr R'RC(-O^-)(MgX)^+`, in which a carbanionic reagent reacts with the carbonyl to effect `C-C` bond formation.