1. Tardigrade
  2. Question
  3. Chemistry
  4. <img class=img-fluid question-image alt=image src=https://cdn.tardigrade.in/img/question/chemistry/ab178fc8aa72df3ff182fc044d021cf1-.png /> <img class=img-fluid question-image alt=image src=https://cdn.tardigrade.in/img/question/chemistry/66bda6ca226c81eaeb946565018cfc76-.png /> The compound (B) is:

Q. image
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The compound (B) is:

Alcohols Phenols and Ethers Report Error

Solution:

i. (A) gives colour with $FeCl _{3}$, suggesting phenolic group.
ii. (A) gives positive Tollens reagent test, suggesting (-CHO) group.
iii. (A) contains only one $(- OH )$ group, since it reacts with $1 mol$ of $CH _{3} I$ to form mono methyl ether.
iv. (A) is not steam distilled, which suggests that $(- OH )$ and (-CHO) groups are not in $o$-position.
v. Total $C$ atom and $O$ atom, $6 C$ (benzene) $+- CHO +(- OH )$ group.
vi. Formula of $(A)=C_{8} H_{8} O_{3}$
vii. To count for one additional $C$ atom and one additional $O$ atom, $\left(- OCH _{3}\right)$ group must be present in (A).
viii. A must contain
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But the compound $F \left( C _{7} H _{6} Br _{2} O _{2}\right)$ contains $Br _{2}$, which is only possible with compound (II). Therefore, structure (A) is (II).
Reaction
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Alternative method of solving the problem:
Start from (D) and proceed reverse to (C). (D) is obtained from (C) by HI, so two structures are possible for (A).
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So, (A) is II and then proceed to find out other products.

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