Patent ID: 8481729

Claim:
A process for the preparation of paliperidone the process comprising: a) treating compound of formula-7 with crystalline solid compound of formula-8 in presence of diisopropylethylamine in alcohol solvent to provide a mixture including paliperidone; b) optionally, treating the mixture obtained in step a) with sodium borohydride to convert any amount of compound of formula-10 formed and present as an impurity, into paliperidone; and c) purifying the paliperidone obtained in step a) or step b) by suspending the paliperidone obtained in step a) or step b) in dichloromethane and treating the suspension with aqueous acetic acid to obtain a dichloromethane layer and an aqueous layer, separating the dichloromethane layer from the aqueous layer and washing the aqueous layer with methyl isobutyl ketone, treating the aqueous layer with hydrose, followed by basifying the aqueous layer with ammonia to provide purified paliperidone.