Target Exam

CUET

Subject

Chemistry

Chapter

Organic: Alcohols, Phenols and Ethers

Question:

An organic compound 'A' with molecular formula CH4O reacts with HI to give an alkyl iodide which than reacts with potassium cyanide to produce 'B'. Compound 'B' on reduction followed by reaction with HNO2 gives an alcohol which on oxidation gives 'C'. Compound 'C' on oxidation followed by reaction with CH3MgBr gives 'D' which on hydrolysis gives compound 'E' which is also an alcohol. 

What is the name of the compound 'E'?

Options:

1-Propanol

2-Propanol

tert-butanol

Butan-2-ol

Correct Answer:

2-Propanol

Explanation:

The correct answer is option 2. 2-Propanol.

Remember

Aldehyde + Grignard → secondary alcohol

Ketone + Grignard → tertiary alcohol

Step 1: Identify A (CH₄O)
CH₄O is methanol (CH₃OH)

CH₃OH + HI → CH₃I (methyl iodide)

Step 2: Formation of B
CH₃I + KCN → CH₃CN (nitrile, B)

Step 3: Reduction of B
CH₃CN → CH₃CH₂NH₂ (primary amine)

Step 4: Reaction with HNO₂
Primary amine + HNO₂ → alcohol

CH₃CH₂NH₂ → CH₃CH₂OH (ethanol)

Step 5: Oxidation to C
Ethanol → Ethanal (CH₃CHO)

Step 6: Reaction with CH₃MgBr
CH₃CHO + CH₃MgBr → secondary alcohol after hydrolysis

Gives: CH₃–CHOH–CH₃

Final compound E:
CH₃–CHOH–CH₃ that is 2-Propanol