The amine that reacts will Hinsberg's reagent to give an alkali insoluble product is

Step-by-step solution

Secondary amines on reaction with Hinsberg's reagent (benzene sulphonyl chloride) forms N , N -dialkyl benzene sulphonamide. The product formed is not acidic as no H -atom is attached to N thus it is insoluble in alkali. The reaction of 2^ amine given in option (1) takes place as follows: On the other hand, 1^ amines react with Hinsberg's reagent to yield N -alkyl benzene sulphonamide which is soluble in alkali and 3^ amines do not react with C ₆ H ₅ SO ₂ Cl . The remaining options contain 1^ and 3^ amines. Thus, o