Table 7. Selected optimization conditions for imidazopyrimidine derivative reaction^a.

Entry	Catalyst (mol%)	Solvent	Temp. (°C)	Timeb (min)	Yieldc (%)
1	1	MeOH	25	10	30
2	1	Water	25	10	90
3	1	ACN	25	10	30
4	1	ACN + toluene	25	10	25
5	1	THF	25	10	35
6	1	CH2Cl2	25	10	25
7	1	MeOH	75	45	35
8	1	ACN	75	45	50
9	1	ACN + toluene	75	45	35
10	1	THF	75	45	40
11	1	CH2Cl2	75	45	38
12	1	Water	75	45	90
13	0.5	Water	25	10	55
14	2	Water	25	10	60
15	—	Water	25	180	14
16	—	Water	75	240	20

^aReaction condition: benzaldehyde (1 mmol), malononitrile (1 mmol), 2-aminobenzimidazole (1 mmol).

^bReaction progress monitored by TLC.

^cIsolated yield.