7. Alcohol, phenol and ethers — Chemistry STD 12 Science — Question

$Pb \left( NO _{3}\right)_{2} \stackrel{673 K }{\longrightarrow} A + PbO + O _{2}$

$A \stackrel{\text { Dimerise }}{\longrightarrow} B$

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In this reaction, $\mathrm{RCONHBr}$ is formed from which this reaction has derived its name. Electron donating group at phenyl activates the reaction. Hofmann degradation reaction is an intramolecular reaction.

$1.$  How can the conversion of $(i)$ to $(ii)$ be brought about?

$(A)$ $\mathrm{KBr}$  $(B)$ $\mathrm{KBr}+\mathrm{CH}_3 \mathrm{ONa}$  $(C)$ $\mathrm{KBr}+\mathrm{KOH}$  $(D)$ $\mathrm{Br}_2+\mathrm{KOH}$

$2.$  Which is the rate determining step in Hofmann bromamide degradation?

$(A)$ Formation of $(i)$  $(B)$ Formation of $(ii)$  $(C)$ Formation of $(iii)$  $(D)$ Formation of $(iv)$

$3.$  What are the constituent amines formed when the mixture of $(i)$ and $(ii)$ undergoes Hofmann bromamide degradation?

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give the answer question $1$, $2$, and $3.$

$C{H_3} - C \equiv CH\xrightarrow{{Excess\,\, HCl}}\left( A \right)\xrightarrow{{{H_2}O/O{H^\Theta }}}\left( x \right)$