Table 4. Comparison for different catalysts used for synthesis of dihyropyrimidinones (4a-4h).

S.No	Catalyst	Reaction condition	Time (h)	Yield (%)	References
1	p-TSA	Refluxed in EtOH	1.0	90	[19]
2	ZnCl2	MW Irradiation	30 sec	94	[20]
3	Zn(BF)4	Stirring at RT	4.0	71	[21]
4	Y(OAC)3	115°C	4.5	89	[22]
5	Mg(NO3)2	Refluxed	45 min	90	[23]
6	CaCl2	Refluxed in EtOH	2.0	98	[24]
7	InBr3	Refluxed in EtOH	7.0	97	[25]
8	Pb(NO3)2	Refluxed in CH3CN	3.0	89	[26]
9	P2O5	Refluxed at 100°C	1.5	94	[27]
10	Citric acid	80°C	1.0	79	[28]
11	Cocos nucifera L. juice	RT	10 min	86	Present work
12	Solanum lycopersicum L. juice	RT	5.0	91	Present work
13	Citrus limetta juice	RT	4.5	93	Present work