8 b]Explain the synthesis of Paracetamol by conventional and green route from phenol.
Paracetamol:
Paracetamol is a common painkiller used to treat aches and pain. It can also be used
to reduce a high temperature. It’s available combined with other painkillers and anti-sickness
medicines. It’s also an ingredient in a wide range of cold and flu remedies
a.] Conventional method: it can be prepared from phenol.
• It is prepared by nitrating phenol with sodium nitrate, to get p-nitro phenol from the orthobyproduct
(p-nitro phenol is retained).
• p-nitro phenol on reduction with sodium borohydride. To give p-aminophenol.
• p-aminophenol on acetylation with acetic anhydride to get the desired product.
b] Green method: it can be prepared from phenol.
• Involves direct acylation of phenol with acetic anhydride in the presence of hydrogen fluoride, to
give intermediate compound.
• Further addition of hydroxyl amine yields oxime bi-product product.
• Oxime product on acylation gives paracetamol.