Draw the compound that would produce 4-ethyl-3-hexanol in the presence of a nickel catalyst and hydrogen.

In organic chemistry, there are already known reaction for synthesis that have been studied and experimented by scientists. For reactions involving a Nickel catalyst in the presence of hydrogen gas, the reaction would be hydrogenation of alkene to yield an alcohol. These reaction is anti-Markovnikov, or proceeds by violating the rule of Markovnikov. His rule states that 'the rich gets richer'. This means that the heavily substituted C atom of the alkene chain would receive another substituent. Therefore, the complete reaction would be

4-ethyl-3-hexene   ------->  4-ethyl-3-hexanol

In structural formula, the reaction goes as follows as shown in the picture.

The answer to that would be magnesium