Table 2.

Michael addition reaction of barbituric acid derivatives 1 to nitroolefin 2 catalyzed by Et₂NH in water at room temperature ^a.

Entry	3	R	Yield (%) b
1	3a	Ph	99
2	3b	p-CH3Ph	96
3	3c	p-BrPh	92
4	3d	p-ClPh	91
5	3e	2,4-Cl2Ph	90
6	3f	2,6-Cl2Ph	91
7	3g	p-CH3OPh	89
8	3h	p-NO2Ph	88
9	3i	Ferrocene	93
10	3j	CH3	96
11	3k	Thiophene	95
12	3l	Ph	97
13	3m	p-CH3Ph	94
14	3n	p-BrPh	88
15	3o	p-ClPh	89
16	3p	2,4-Cl2Ph	85
17	3q	2,6-Cl2Ph	86
18	3r	p-CH3OPh	88
19	3s	Ferrocene	92
20	3t	p-NO2Ph	87

^a All reactions were carried out with barbituric acid 1 (1.5 mmol), nitroalkene 2 (1.5 mmol) and amine (1.5 mmol) in water (1.5 mL) for the specified time. ^b Yield of isolated product.