Concept explainers
(a)
Interpretation: The mechanism for the formation of compound A has to be proposed.
Concept Introduction:
Diels-Alder reaction:
It is the reaction of conjugated dienes with double or triple bonded compounds which are known as “dienophiles”. The reaction is a
Example:
This mechanism shown that three
Formation of Benzyne:
The elimination of two halogens from the halobenzene forms the most reactive neutral intermediate with triple bond which is known as Benzyne intermediate.
Diels-Alder reaction with Benzyne intermediate:
The reaction of Benzyne with furan serves as an example for this reaction:
Benzyne is an extremely reactive species because of the presence of triple bond in it. It undergoes Diels-Alder reaction in which it acts as dienophile and reacts with furan which acts a diene. The resulted product will be a tricyclic product which is known as Diels-Alder adduct.
(b)
Interpretation: Using the given sources, the conversion of compound (A) into Tolciclate has to be shown.
Concept Introduction:
Acidic hydrolysis of ether:
Ether on hydrolysis gets converted into two moles of alcohols of same type in the case of symmetrical ether and of different types in the case of unsymmetrical ether. .
General scheme for symmetrical ether:
General scheme for unsymmetrical ether:
Tosylation reaction:
When an alcohol is treated with any tosyl chloride (methane sulfonyl chloride) it gets converted into tosylated product and this reaction is called as Tosylation reaction which is shown below:
The reaction of acetyl chloride with
The acyl group of acetyl chloride is very reactive and the chloride group attached to it is a good leaving group. The nucleophile from amine attacks the carbonyl carbon of the acetylchloride to form N- methylacetamide. The chloride group leaves and gets attached to hydrogen of the amine and leaves as hydrochloric acid.
The reaction is:
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EP ORGANIC CHEMISTRY-OWL V2 ACCESS
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