Question

How will you convert 3-ethyl-2-pentene to 3-ethylpentane?

Answer 1

Hint: The reduction reaction reduces alkene to alkane. But those are very specific in accordance with the types of alkenes they are reducing.

Complete step by step answer:
Let us learn about the reduction reactions which convert alkenes to alkanes.
Hydrogenation is the alkene addition reaction in which alkene undergoes reduction to form alkane. In hydrogenation of alkene hydrogen atoms are added across the double bond resulting into a single bond and hence, saturated alkane is formed.
Catalysts are required for this type of reductions. Three metals are used to derive catalysts which make addition of hydrogen and alkene groups easier.
Nickel- in the form of Raney nickel; prepared by reacting Ni-Al alloy with NaOH.
Palladium- supported on an inert substance as charcoal (Pd/C). Here the alkene is dissolved in ethanol when Pd/C is used as a catalyst.
Platinum- used as $Pt{{O}_{2}}$ (Adam’s catalyst). Solvent used for alkene is ethanol or acetic acid.
The most widely used catalyst is the Raney nickel catalyst (spongy nickel catalyst) as its stable and highly catalytic at room temperature. It reduces alkynes, alkenes, dienes, aromatics and carbonyl-containing compounds.

The given conversion is of 3-ethyl-2-pentene to 3-ethylpentane:
This is achieved by ${{H}_{2}}/Ni$ reduction. The Raney nickel catalyst reduces double bond in 3-ethyl-2-pentene to single bond in 3-ethylpentane.
The reaction is taking place at 150${}^\circ $C as,

Therefore, we can convert 3-ethyl-2-pentene to 3-ethylpentane by reduction using Raney nickel catalyst.

Note: Raney nickel is stable but is also extremely flammable when contacted with air. So, it is usually stored in water. Precautions must be taken while using it as a catalyst.