Question

the reagents used in the conversion are

• A. (i) $PBr_3$ (ii) $NH_3$
• B. (i) red P, $Br_2/$ (ii) $NH_3$ (excess)
• C. (i) $PBr_3$, NaCN/ (ii) $LiAlH_4$
• D. None of the above

Answer 1

Answer: (B)

(i) red P, $Br_2/$ (ii) $NH_3$ (excess)

Answer 2

In this reaction, $\alpha$-bromo or chloro acids are prepared by the reaction of carboxylic acid with bromine or chlorine in presence of small amount of red phosphorus.