A comparison of the catalytic activity of the (Fe₃O₄@NFC@NSalophCu)CO₂H catalyst with some reported catalysts for tetrazole multi-component reactions.

Reaction	Catalyst	Reaction conditions	Time (h)	Yielda (%)	Ref.
1-Substituted-1H-tetrazoleb	Natrolite zeolite	Neat/120 °C	4	82	72
	In(OTf)3	Neat/100 °C	1.5	89	73
	Silica sulfuric acid	Neat/120 °C	5	95	74
	Fe3O4@SiO2@salen@Cu	Neat/100 °C	1	96	7
	Fe3O4@quindiol@Cu	Neat/100 °C	0.66	92	75
	ZnS nanoparticles	DMF/R.T.	0.5	92	76
	Fe3O4@HT@AEPH2–CoII	H2O/90 °C	1	95	77
	ZnS nanoparticles	Neat/130 °C	4.5	78	78
	Cu NPs/bentonite	Neat/120 °C	3	93	79
	(Fe3O4@NFC@NSalophCu)CO2H	Neat/80 °C	0.33	98	This work

^aIsolated yield.

^bReaction conditions: aniline (1.0 mmol), triethyl orthoformate (1.2 mmol), and sodium azide (1.2 mmol).