Question

Select the correct statement(s) for the following.

• A. Nitriles are hydrolysed to amides and then to acids in the presence of $H ^{+}$or $OH ^{-}$as catalyst
• B. Mild reaction conditions are used to stop the reaction at the amide stage during the hydrolysis of nitriles
• C. Grignard reagents react with dry ice to form salts of carboxylic acids which in turn give corresponding carboxylic acids after acidification with mineral acid
• D. All of the above

Answer 1

Answer: (D)

Nitriles are hydrolysed to amides and then to acids in the presence of $H ^{+}$or $OH ^{-}$as catalyst. Mild reaction conditions are used to stop the reaction at the amide stage.
$R- CN \xrightarrow[H_2O]{ H ^{+} \text {or } OH ^{-}} R CONH _{2} \xrightarrow[ \Delta]{ H ^{+} \text {or } OH ^{-}} R COOH$
Grignard reagents react with carbon dioxide (dry ice) to form salts of carboxylic acids which in turn give corresponding carboxylic acids after acidification with mineral acid.
$R- Mg X+ CO _{2} \xrightarrow[\text{ether}]{\text { Dry }}R- COO ^{-} Mg X \xrightarrow{ H _{3} O ^{+}} R COOH$