Optimizing of the reaction conditions for the synthesis of 2h^a.

Entry	Solvent	Temperature (°C)	Catalyst loading (mg)	Time (min)	Yieldb (%)
1	—	90	10	10	92
2	—	80	15	10	90
3c	—	70	10	10	91
4		70	5	30	80
5	—	70	—	10	Trace
6	—	70	7	10	82
7	—	70	20	10	92
8	—	70	—	120	60
9	—	60	10	30	70
10	—	50	10	100	20
11	H2O	Reflux	10	60	—
12	EtOH	Reflux	10	60	45
13	n-Hexane	Reflux	10	60	—
14	EtOAc	Reflux	10	60	50
15	CH2Cl2	Reflux	10	60	—

^aReaction conditions: 4-cholorobenzaldehyde (1 mmol, 0.140 g), 5,5-dimethylcyclohexane-1,3-dione (1 mmol, 0.140), ethyl acetoacetate (1 mmol, 0.130 g), ammonium acetate (1 mmol, 0.078 g).

^bRelated to isolated yields.

^cOptimal data.