Poly(4-Vinylpyridinium)Hydrogen Sulfate Catalyzed an Efficient and Ecofriendly Protocol for the One-Pot Multicomponent Synthesis of 1,8-Acridinediones in Aqueous Medium

Table 1

Optimizing the reaction conditions^a.

Entry	P(4-VPH)HSO4 (g)	Temperature (°C)	Time (min)	Yield^b (%)
1	—	RT	120	—
2	—	80	120	28
3	—	Reflux	120	36
4	0.01	RT	60	Trace
5	0.01	80	30	74
6	0.01	Reflux	30	74
7	0.02	80	10	95
8	0.02	Reflux	10	95
9	0.03	80	10	94
10	0.03	Reflux	10	92

^aDimedone (2 mmol), p-chlorobenzaldehyde (1 mmol), ammonium acetate (3 mmol), and P(4-VPH)HSO₄ in aqueous medium.
^b Isolated yields.