Question

In a reaction,

 reagents ' X ' and ' Y ' respectively are :

• A. \(CH _3 OH / H ^{+}, \Delta and CH _3 OH / H ^{+}, \Delta\)
• B. \(\left( CH _3 CO \right)_2 O / H ^{+}and CH _3 OH / H ^{+}, \Delta\)
• C. \(\left( CH _3 CO \right)_2 O / H ^{+} and \left( CH _3 CO \right)_2 O / H ^{+}\)
• D. \(CH _3 OH / H ^{+}, \Delta and \left( CH _3 CO \right)_2 O / H ^{+}\)

Hint:

Recognize the functional groups involved and the type of reaction taking place. Fischer esterification is a common method for preparing esters from carboxylic acids or phenolic OH groups.

Answer 1

The Correct Option is B

The reaction sequence involves the transformation of functional groups. Let's analyze the steps and identify the reagents 'X' and 'Y'.

Step 1: Conversion with reagent 'X'

The compound with an -OH group needs to be transformed into an acetylated product. This transformation requires acetylation, typically done using acetic anhydride \(\left( CH_3CO \right)_2O \) in the presence of an acid catalyst such as \(H^+\). This reagent will convert the phenolic -OH group to an acetate group \((-OC(O)CH_3)\).

Step 2: Conversion with reagent 'Y'

The next step involves converting the ester group \(COOCH_3\) back to a carboxylic acid group \(COOH\). This transformation usually requires acidic conditions along with heat, using methanol (\(CH_3OH\)) and \(H^+\) in combination with heat \(\Delta\).

Thus, the correct reagents are \( \left( CH_3CO \right)_2O / H^+\) for 'X' and \(CH_3OH / H^+, \Delta\) for 'Y'.

Conclusion:

The correct option is: \(\left( CH_3CO \right)_2O / H^+ \text{ and } CH_3OH / H^+, \Delta\).