Question

Describe how 3-methyl-1-phenyl-3-pentanol can be prepared from benzene. You can use any inorganic reagents and solvents, and any organic reagentsprovided they contain no more than two carbons.

Short answer

3-methyl-1-phenyl-3-pentanol can be prepared from benzene by doing thefollowing reactions:friedal-craft alkylation reaction, dehydrohalogenation, hydrolysis, and treating with Gilman and Grignard reagent.

Step-by-step solution

Reagent and Solvent

Reagents and solvents arecompounds added to an organic reaction to cause the chemicalchange. The reaction has the same reactant, but the product can vary due to the difference in a solvent and reagent.

Reagent and solvent play a very important role indeciding any organic reaction product

Preparation of 3-methyl-1-phenyl-3-pentanol

Preparation of 3-methyl-1-phenyl-pentanol starting with benzene is done as follows:

• Benzene undergoes a friedal-craft alkylationreaction to form ethylbenzene, reacting with NBS to form 1-(bromoethyl) benzene.
• 1-(bromoethyl) benzene reacts with alkaline potassium hydroxide, which undergoes dehydrohalogenation to form the styrene, reacts with HBr in the presence of peroxide forms 2-(bromoethyl) benzene.
• 2-(bromoethyl) benzene reacts with KCN, followed by hydrolysisforms 3-phenylpropanoic acid.
• 3-phenylpropanoic acid reacts with thionyl chloride to form a 3- phenylpropanoyl chloride, which reacts with Gilman reagentto form 4-phenylbutan-2-one.
• 3-phenylpropanoic acid reacts withethylmagnesium bromide, followed by hydrolysis forms the desired product 3-methyl-1-phenyl-3-pentanol.