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Reduction

In organic compounds carbon displays different oxidation states. One can thus transform a functional group into another by either reduction or oxidation.

Depending on where we are in the 'redox tree' and where we want to go, we will use either a reduction or an oxidation.

'Redox tree': oxidation states of carbon from C4− (alkanes) to C4+ (CO₂), through alkenes and alcohols, alkynes, aldehydes and ketones, and acids and derivatives

The reduction of aldehydes and ketones can be accomplished in two different ways:

Catalytic hydrogenation of aldehydes and ketones: 3-methylpentanal gives 3-methyl-1-pentanol with H₂/Pd and cyclohexanone gives cyclohexanol with H₂/Pt
Reduction with hydrogen (catalytic hydrogenation)
Selectivity of hydrides: NaBH₄ in methanol reduces the ketone of ethyl 2-oxocyclopentanecarboxylate without touching the ester; LiAlH₄ reduces both groups
Reduction with metal hydrides (NaBH4 and LiAlH4)

Can you say anything about the 'selectivity' of the two hydrides? Which one is more chemoselective?