Question

explain HVZ reaction with an example​

Answer 1

HVZ reaction is haogenation of carboxylic acids at alpha carbon atom. In this reaction red-P and bromine is treated with carboxylic acids having alpha hydrogen atom followed by hydrolysis to form alpha bromo carboxylic acid. Initially red phosphorus and bromine reacts with each other to give PBr₃.

HVZ Reaction or Hell-Volhard Zelinsky Reaction

Carboxylic Acids react with chlorine molecule (Cl2) or bromine molecule (Br2) to form α-substituted carboxylic acids. The reaction takes place in the presence of red phosphorus. This reaction refers to as H.V.Z reaction or Hell-Volhard Zelinsky Reaction.