Question

Choose the reagent and reactant that would produce 2-methyl-2-butanol as the major product.

• A. Only I
• B. Both I and III
• C. I, II and III
• D. Only III

Answer 1

The correct option is C I, II and III

2-methyl-2-butanol is a tertiatiary
($3^{\circ }$) alcohol.
Grignard reagent react with ketones and ester to form $3^{\circ }$ alcohol.
Reactants of options I and II are ketones and option III is an ester. So all of them can form 2-methyl-methylbutanol with appropriate reagents.
Option II and III have 4 carbon chain and need methyl Grignard reagents while option I has 3 carbon chain and need ethyl Grignard reagent.

All of the above reactions give 2-methyl-2-butanol. Hence correct option is c.