Question

The suitable Grignard reagent used for the preparation of 2-methylpropan-1-ol using methanal is

• A. $CH_3-CH(CH_3)-MgBr $
• B. $CH_3-CH_2-CH_2-CH_2MgBr $
• C. $CH_3-CH(CH_2)-CH_2MgBr $
• D. $ (CH_3)_3 C-MgBr $
• E. $ CH_3-CH_2-CH_2MgBr$

Answer 1

The Correct Option is A

To prepare 2-methylpropan-1-ol using methanal and a Grignard reagent, we follow this reaction:

\( \text{HCHO} + \text{R–MgBr} \xrightarrow{\text{ether}} \text{R–CH}_2\text{OH} \)

The required product is 2-methylpropan-1-ol, which has the structure:

\( \text{CH}_3–\text{CH(CH}_3)–\text{CH}_2\text{OH} \)

This shows that the R group in the Grignard reagent should be isopropyl \( (\text{CH}_3–\text{CH(CH}_3)–) \).

So, the correct Grignard reagent is:

\( \text{CH}_3–\text{CH(CH}_3)–\text{MgBr} \)

Correct Answer:

Option (A): \( \text{CH}_3–\text{CH(CH}_3)–\text{MgBr} \)