NiO Nanoparticles: An Efficient Catalyst for the Multicomponent One-Pot Synthesis of Novel Spiro and Condensed Indole Derivatives

Table 4

Optimization of reaction conditionsa.

Entry	Catalysts (mg)	Yield (%)
1	10	83
2	20	90
3	30	90

^aThe reaction was carried out with 1H-indole-2,3-dione, malononitrile and 2-thioxo-4-thiazolidinone under microwave irradiation.