Question

Reaction RCOOAg $\xrightarrow{Br_{2}/CCl_{4}}$ RBr is called:

Hint:

Hunsdiecker reaction shortens the carbon chain by one carbon when converting carboxylic acids to alkyl halides.

Answer 1

Step 1: Recall the Hunsdiecker reaction.
In the Hunsdiecker reaction, silver salts of carboxylic acids (RCOOAg) react with bromine in the presence of CCl$_4$ to yield alkyl bromides (RBr) with the loss of one carbon atom.

Step 2: Analyzing the options.
- (A) Hunsdiecker reaction: Correct, this is exactly the given reaction.
- (B) Schmidt reaction: Converts carboxylic acids to amines using hydrazoic acid, not applicable here.
- (C) Hell-Volhard-Zelinsky reaction: Involves halogenation at the $\alpha$-position of carboxylic acids, different from the given case.
- (D) Tishchenko reaction: Forms esters from aldehydes, unrelated.

Step 3: Conclusion.
Thus, the given reaction is called the Hunsdiecker reaction.

Final Answer: \[ \boxed{\text{(A) Hunsdiecker reaction}} \]