Table 1.

Optimizing the three-component reaction of 4-chlorobenzaldehyde (2a), malononitrile (3), and dimedone (4a) under various conditions.

.

Entry	Catalyst loading	Solvent	Temp. (°C)	Time (min)	Yieldb (%)
1	0.04	THF	75	360	68
2	0.04	MeCN	75	300	85
3	0.04	EtOH	75	20	90
4	0.04	EtOH	50	30	85
5	0.04	EtOH	r.t	45	80
6	–	Solvent-free	r.t	80	88
7	0.02	Solvent-free	r.t	26	90
8	0.04	Solvent-free	r.t	5	96
9	0.04	Solvent-free	r.t	20	78

^a Conditions of reaction: 4-chlorobenzaldehyde (2a, 1.0 mmol), malononitrile (3, 1.0 mmol), dimedone (4a, 1.0 mmol), grinding, ambient temperature.

^bYield refers to isolated products.