(b) How would you prepare following compounds from an internal alkyne? Give the mechanism of the reactions.

(i) 3-Hexanone

(ii) Ethanoic acid

(i) 3-Hexanone can be prepared from an internal alkyne through a two-step process involving hydroboration-oxidation and subsequent oxidation.

1. Hydroboration-Oxidation:
   Start with the internal alkyne, such as 3-hexyne. React it with borane (BH3) and tetrahydrofuran (THF) in the first step. The hydroboration reaction adds a boron atom to the less substituted carbon, forming an alkylborane. In this case, it will add to the triple bond, giving you 3-hexenylborane.

   Mechanism:
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