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JEE Main 202430 JanuaryMorning Shift
Exam
JEE Main
Year
2024
Date
30 January
Shift
Morning Shift
Subject
Chemistry
Chapter
Hydrocarbons

JEE Main 2024 · 30 January · Morning Shift · Chemistry · Hydrocarbons

In the given reactions identify the reagent A and reagent B

In the given reactions identify the reagent AA and reagent BB

In the given reactions identify the reagent A and reagent B

Options

  1. AA−CrO3B−CrO3A - {CrO}_{3}B - {CrO}_{3}
  2. BA−CrO3B−CrO2Cl2A - {CrO}_{3}B - {CrO}_{2}{Cl}_{2}
  3. CA−CrO2Cl2B−CrO2Cl2A - {CrO}_{2}{Cl}_{2}B - {CrO}_{2}{Cl}_{2}
  4. DA−CrO2Cl2B−CrO3A - {CrO}_{2}{Cl}_{2}B - {CrO}_{3}

Correct answer

B. A−CrO3B−CrO2Cl2A - {CrO}_{3}B - {CrO}_{2}{Cl}_{2}

Step-by-step solution

Toluene or substituted toluene is converted to benzylidene diacetate on treating with chromic oxide in acetic anhydride. The benzylidene diacetate can be hydrolysed to corresponding benzaldehyde with aqueous acid.

Chromyl chloride oxidises
methyl group to a chromium complex, which on hydrolysis
gives corresponding benzaldehyde. The reaction is known as Etard reaction.

In the given reactions identify the reagent A and reagent B

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