Write structure of the products of the following reactions:
Write structure of the products of the following reactions:
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Solution and Explanation
(a) Anisole (methoxybenzene) reacts with HI.
HI protonates the ether oxygen and breaks the C–O bond.
The methyl group leaves as methyl iodide (CH$_3$I) and phenol (C$_6$H$_5$OH) is formed.
So, products are: Phenol + CH$_3$I.
(b) Phenol activates the benzene ring strongly towards electrophilic substitution.
With concentrated nitric acid, multiple nitro groups attach to ortho and para positions.
So, 2,4,6-trinitrophenol (picric acid) is formed.
This reaction is an example of nitration of an activated aromatic compound.
(c)The Grignard reagent (Cyclohexyl–MgBr) attacks the carbonyl carbon of formaldehyde.
This forms an alkoxide intermediate.
On acid hydrolysis, the alkoxide is protonated to give a primary alcohol.
So, the product is cyclohexylmethanol (Cyclohexane–CH$_2$–OH).
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What is meant by the following terms? Give an example of the reaction in each case.
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\((ii)Acetal \)
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\((v)\)
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