4-nitrotoluene is treated with \({\mathrm{Br}}_{2}\) to get compound P which is reduced with Sn and HCl to get Compound …

4-nitrotoluene is treated with \({\mathrm{Br}}_{2}\) to get compound P which is reduced with Sn and HCl to get Compound Q, then Q is diazotized and the product is treated with phosphinic acid to get R is oxidized with alkaline \({\mathrm{KMnO}}_{4}\) to get the final product

(JEE mains memory based shift-1 23/01/2025)