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

Table 1

Synthesis of Spiro and condensed indole derivatives under microwave irradiation using Ni₁₀₀ nanoparticles.

Entry	R	X	Time (min.)	Product	Yield (%)	MP (°C)
					NiO100/Piperidine
5a	H	CN	8		90/75	298
5b	5-Cl	CN	8		87/72	310
5c	7-Cl	CN	9		87/74	275
5d	5-Br	CN	8		88/72	270
5e	5-NO2	CN	10		90/72	340
5f	5-CH3	CN	8		88/70	315
5g	H	COOEt	8		89/74	332
5h	5-Cl	COOEt	9		87/73	288
5i	7-Cl	COOEt	10		88/73	226
5j	5-Br	COOEt	9		88/72	347
5k	5-NO2	COOEt	9		84/74	265
5l	5-CH3	COOEt	10		87/71	356

NiO₁₀₀ is the nanoparticle calcined at 100°C.