Q. In the following reaction $RCH_{2}COOH\overset{\ \ \ Br_{2}/P\ \ \ \ }{\rightarrow}X\overset{\ \ Excess\ NH_{3}\ \ \ }{\rightarrow}Y$ The major amounts of X and Y are
A) $RCHBrCONH_{2};RCH(NH_{2})COOH$
B) $RCHBrCOOH;RCH(NH_{2})COOH$
C) $R{CH}_{2}COBr;R{CH}_{2}{COONH}_{4}$
D) $RCHBrCOOH;R{CH}_{2}{CONH}_{2}$
Explanation
(b)
When an acid is heated with $Br_{2}$ in presence of P,$\ \alpha -$H atom of the acid is replaced by bromine atom. This reaction is called Hell-Volhard Zelinsky reaction. $NH_{2}^{-}$ is a better nucleophile than$Br^{-}$.
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Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.