Question

Which of the following alkyl halide cannot be converted into Grignard reagent?

• A. $C_6{H}_{5}Br$
• B. $C{H}_{3}C{H}_{2}C{H}_{2}C{H}_{2}Cl$
• C. $C{H}_{3}I$
• D. $HOC{H}_{2}C{H}_{2}C{H}_{2}Cl$

Answer 1

The correct option is D $HOC{H}_{2}C{H}_{2}C{H}_{2}Cl$

Magnesium can be reacted with alkyl halides or aryl halides to form Grignard reagents. The organic halide is added to a magnesium suspension in an dry ether solvent. It is important to note that the reagent can be made with alkyl chlorides, bromides, and iodides but not with fluorides. Halides containing acidic hydrogen (here - OH) cannot be used in Grignard's synthesis. Grignard reagent consists of very basic carbanion (R) and will react with acidic hydrogen. Hence, the correct answer will be option (c).