Question

The following is the reaction sequence of the substrate isobutylbenzene.
Predict the products A, B, C, & D. The final product is

• A. Ibuprofen
• B. an analgesic
• C. anti-pyretic
• D. a non-steroidal anti-inflammatory drug (NSAID)

Answer 1

Answer: (A), (B), (C), (D)

a non-steroidal anti-inflammatory drug (NSAID)

Let us start with isobutyl benzene. First step to A is the Friedel-Crafts acylation, which is followed by hydroboride reduction:

The isobutyl group is abbreviated as i-Bu as shown. The OH group is replaced by the Br group, which is in turn displaced by CN group.
The nitrile is hydrolysed to give the acid – which goes by the drug name ibuprofen. It is both an analgesic and an anti-pyretic.