63E - Organic Chemistry (Mcmurry)

Question

How would you carry out the following transformations? More than one step is needed in each case.

Step-by-Step Solution

Answer

The transformation for the below structures has been shown.

Step 1: Transformation steps for the conversion of benzene into 2-methyl-2-phenylpropanoic acid

The treatment of Friedel-Crafts alkylation with isopropyl chloride with anhydrous AlCl₃ will yield isopropyl benzene. The isopropyl benzene will brominate in benzyl carbon by treating with NBS for the production of 2-Bromo-2-phenylpropane in presence of (PhCO₂)₂. The production of Grignard reagent can be done when treated with Mg. The conversion of Grignard reagent into 2-methyl-2-phenylpropanoic acid when treated with CO₂ and involve hydrolysis.

Step 2: Conversion structure of Benzene into 2-methyl-2-phenylpropanoic acid

The structure can be drawn as,

Step 3: Steps for the conversion of cyclohexanone to 1-phenylcyclohexanecarboxylic acid

The treatment of cyclohexanone with phenylmagnesium bromide and gets hydrolyzed into 1-phenylcyclohexanol with aqueous acid. The alcohol will be converted into 1-Bromo-1-phenyl cyclohexane when treated with HBr. The bromide will be converted into Grignard reagent when treated with Mg. The reaction of the Grignard reagent with CO₂ and the product will yield 1-phenylcyclohexanecarboxylic acid.

Step 4: Structure for the conversion of cyclohexanone to 1-phenylcyclohexanecarboxylic acid

The structure can be drawn as,