Which of the following compounds will react with two moles of CH3MgBr ?

Question

Which of the following compounds will react with two moles of CH3MgBr ? (A) C2H5COOH  (B) CH3COOH  (C) CH 3 C ≡ CCH 3 (D) HC ≡ C - CH 2 OH

Tardigrade Admin · Accepted Answer

Reaction of carboxylic acid with Grignard is shown above.
It'll only consume 1 mole of

C H_{3} M g B r

.

C H_{3} C \equiv CC H_{3}

won't react with Grignard reagent because it doesn't have active H-atom.
In

H C \equiv C - C H_{2} O H

two active hydrogen atoms are present, hence it will react with two moles of

C H_{3} M g B r

(Grignard reagent) as shown below.

H C \equiv C - C H_{2} O H + 2 C H_{3} M g B r \to 2 C H_{4} + B r M g C \equiv CC H_{2} OM g B r

Q. Which of the following compounds will react with two moles of $C H_{3} M g B r$ ?