Looking for classes? Ksquare Career Institute, Bengaluru →

2022 Aldehydes, Ketones and Carboxylic Acids Preparation of Carboxylic Acids – Grignard Reagent Medium Question 19 of 91 in Aldehydes, Ketones and Carboxylic Acids

$RMgX+CO_2\xrightarrow{dry\ ether}Y\xrightarrow{H_3O^+}RCOOH$. What is Y in the above reaction?

A $(RCOO)_2Mg$

B $RCOO^-Mg^+X$

C $R_3CO^-Mg^+X$

D $RCOO^-X^+$

The answer is B.

Solution

The Grignard reagent adds to $CO_2$: $RMgX + O=C=O \rightarrow R-COO^-\,{}^+MgX$ (Y) $R-COOMgX \xrightarrow{H_3O^+} R-COOH$ So Y is $RCOO^-Mg^+X$.

Concept intermediate in Grignard carboxylation

Aldehydes, Ketones and Carboxylic Acids in past papers

91 questions from this chapter have appeared across 27 exam years.