Table 4. Comparison of E with other catalysts for the synthesis of a(1–12).

Entry	Catalyst	Conditions	Time (min)	Yield (%)	Ref.
1	p-TSOH	Solvent-free, 120 °C	2 h	84	26
2	Fe3O4@C/Ph SO3H	H2O, 80 °C	1 h	96	27
3	g-C3N4/NHSO3H	i-PrOH, 80 °C	4 h	95	28
4	NaN3, Hg(OAc)2	HOAc, 100 °C	6 h	67	29
5	AlCl3	CH3CN, reflux	3 h	92	30
6	I2	i-PrOH, reflux	10 min	92	42
7	p-TSA	Solvent-free, 70 °C	6 min	88	43
8	MNPs@SiO2-Pr ANDSA	EtOH/H2O, 100 °C	5 min	94	44
9	PyTFA	μW, 90 °C	25 min	93	45
10	Our catalyst	Solvent-free, 70 °C	5 min	90	This work