The solvent-free, microwave (MW)-assisted synthesis of a new series of 3′-(aryl/heteroaryl)-1-morpholinomethyl/piperidinomethylspiro[3H-indole-3,2′-thiazolidine]-2,4′(1H)-diones has been achieved in an open vessel. Isatins undergo an easy condensation with various aryl/heteroaryl amines by MW using montmorillonite K10 clay as a solid support to afford Schiff bases , which subsequently undergo smooth