DBU-catalyzed tandem annulation of arylhydrazonopropanals 1a–o with acetoacetanilide 2 under conventional and microwave conditions^a.

Entry	Products	R	Ar	Thermal (2 h)		MW (3 min)
				Yieldb		Yieldb
				3	4	3	4
1	3a/4a	4-NO2C6H4	4-BrC6H4	84	10	95	Trace
2	3b/4b	4-NO2C6H4	4-ClC6H4	80	13	93	Trace
3	3c/4c	4-NO2C6H4	3-ClC6H4	78	16	90	Trace
4	3d/4d	4-NO2C6H4	C6H5	72	20	83	10
5	3e/4e	4-ClC6H4	C6H5	62	28	70	22
6	3f/4f	4-ClC6H4	4-BrC6H4	74	18	86	8
7	3g/4g	4-BrC6H4	4-ClC6H4	66	25	75	16
8	3h/4h	4-BrC6H4	4-BrC6H4	67	25	75	18
9	3i/4i	4-FC6H4	4-ClC6H4	75	18	88	Trace
10	3j/4j	4-FC6H4	4-BrC6H4	76	18	88	Trace
11	3k/4k	4-OMeC6H4	4-BrC6H4	52	38	60	28
12	3l/4l	4-OMeC6H4	o-NO2C6H4	55	35	64	24
13	3m/4m	C6H5	4-ClC6H4	62	27	70	20
14	3n/4n	C6H5	4-BrC6H4	60	30	70	18
15	3o/4o	C6H5	o-NO2C6H4	70	20	83	10

^aReaction condition: 1a–o (0.5 mmol), acetoacetanilide 2 (0.5 mmol), DBU (0.3 mmol) in 1,4-dioxane (6 mL), at 40 °C for 2 h (thermal heating), and 40 °C (200 W) for 3 min (microwave irradiation).

^bIsolated yields of 3 and 4.