Question

12. A student added one equivalent of 3,4-epoxy-4-methylcyclohexanol to a solution of methylmagnesium bromide in diethyl ether, and then added dilute hydrochloric acid. He expected that the product would be 1,2-dimethylcyclohexane-1,4-diol. He did not get this expected product. Draw the structures of 3,4-epoxy-4-methylcyclohexanol, methylmagnesium bromide, and 1,2- dimethylcyclohexane-1,4-diol. Explain why the student did not get his expected product. What organic product(s) did he get? Show all reaction steps for better yet, show the reaction mechanisms). CH, MgBr CH4 att HOH

Answer 1

1. So to the solution of 3,4-epoxy-4-methylcyclohexanol students was added methyl magnesium bromide so instead of attacking epoxide grignard reagent pick the hydroxy proton and formed methane gas.

mechanism! - CH. MB + C 1 H . Step 1 ngor OH 04

2. Then after addition of aqueous HCl epoxide got protonated and water molecules attacking on epoxide which will opens up two form diole.

So students got undesired product instead of 1,2-dimethylcyclohexane-1,4-dole.