After the preparation of isobutyl benzene, It is used for the historic synthesis of ibuprofen developed...

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After the preparation of isobutyl benzene, It is used for the historic synthesis of ibuprofen developed the Boots company. This company originally had discovered the analgesic activity of this compound. A full synthetic scheme is presented below. The synthesis begins with another Friedel-Crafts acylation on isobutylbenzene with acetyl chloride to give (4). The next synthetic steps work to convert this compound's para-acetyl group to ibuprofen's propionic acid substituent. First, The acetyl group is converted to an a,ß-epoxy ester (5) via a Darzens reaction with ethyl chloroacetate. Next, hydrolysis and decarboxylation give the aldehyde (6). Condensation with hydroxylamine affords an aldoxime (7) which is then dehydrated to the nitrile (8) using acetic anhydride. Lastly, acid-catalysed hydrolysis of the nitrile to a carboxylic acid yields ibuprofen. OEt AICI, NaOEt Isobutylbenzene (2) OEt H,0", A Ac,0, A N- -OH NH,OH (8) H. H;O", A он IЬuprofen (d) Discuss the synthetic pathway for the synthesis of Ibuprofen. (10 marks) After the preparation of isobutyl benzene, It is used for the historic synthesis of ibuprofen developed the Boots company. This company originally had discovered the analgesic activity of this compound. A full synthetic scheme is presented below. The synthesis begins with another Friedel-Crafts acylation on isobutylbenzene with acetyl chloride to give (4). The next synthetic steps work to convert this compound's para-acetyl group to ibuprofen's propionic acid substituent. First, The acetyl group is converted to an a,ß-epoxy ester (5) via a Darzens reaction with ethyl chloroacetate. Next, hydrolysis and decarboxylation give the aldehyde (6). Condensation with hydroxylamine affords an aldoxime (7) which is then dehydrated to the nitrile (8) using acetic anhydride. Lastly, acid-catalysed hydrolysis of the nitrile to a carboxylic acid yields ibuprofen. OEt AICI, NaOEt Isobutylbenzene (2) OEt H,0", A Ac,0, A N- -OH NH,OH (8) H. H;O", A он IЬuprofen (d) Discuss the synthetic pathway for the synthesis of Ibuprofen. (10 marks)