rationalize-why-the-carbonyl-oxygen-of-the-ester-attacks-the-aluminum-of-dibal-h

Question

Rationalize why the carbonyl oxygen of the ester attacks the aluminum of DIBAL-H instead of the alkoxy oxygen in the following reaction.

Reaction diagram showing DIBAL-H interacting with an ester's carbonyl oxygen.

Accepted Answer

The resonance hybrid of the ester shows that the carbonyl oxygen of the ester is more nucleophilic than the alkoxy oxygen.

Answer

The resonance hybrid of the ester shows that the alkoxy oxygen of the ester is more nucleophilic than the carbonyl oxygen.

Answer

The carbonyl oxygen is sterically less hindered hence it can more easily attack aluminum.

Answer

None of these.