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Reimer Tiemann Reaction

a Write a sho...

Question

a) Write a short note on Reimer- Tiemann reaction.
b) Two isomeric compounds (A) and (B) have molecular formula $C_{7} H_{7} O H$ (A) gives violet colour with neutral ferric chloride solution whereas (B) does not. Suggest structures for (A) and (B)

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Solution

a) Reimer-Tiemann reaction: When the phenol is treated with chlorophyll in presence of aqueous sodium or potassium hydroxide at 340 K followed by hydrolysis of the resulting product gives 2-hydroxybenzaldehyde as the major product. This reaction is called the Reimer-Tiemann reaction.
b) In the above image, structure (1) is A and structure (2) is B. We can see that the structure(1) has Oh group directly attached to the aromatic ring creating an " enol" system which shows violet colour with ferric chloride solution while the benzyl alcohol will not show any reaction with the solution.

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C_{6} H_{6} O

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Q. (a) An organic compound (A) of molecular formula

C_{6} H_{6} O

gives violet colour with neutral ferric chloride. Compound (A) when refluxed with

C H {C l}_{3}

N a O H

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(b) Compound (A) is an orange red crystal and also a powerful oxidising agent. Compound (A) when treated with potassium chloride and concentrated sulphuric acid evolves coloured gas (B). When

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Q. An organic compound (A) with molecular formula

C_{8} H_{8} O

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C_{7} H_{5} O C l

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R_{2} C d

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Q. Two isomeric compounds

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C_{3} H_{6} C l_{2}

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