The synthesis of pyridine derivatives (1a–15a) catalyzed by ETG-acetamide^a.

Entry	R	Ketone	Product	Time (h)	Yielda (%)	Mp. (°C)	Ref.
1a	H			3	71b	242–244	237–239 (ref. 44)
2a	4-OMe			3	47b	239–240	234–236 (ref. 45)
3a	4-Cl			3	33b	266–268	260–261 (ref. 45)
4a	4-F			3.5	58b	259–260	—
5a	2-Cl			3	46b	259–261	254–257 (ref. 46)
6a	2-F			3	44b	254–256	—
7a	4-Br			3	53b	299–301	255–257 (ref. 45)
8a	4-Me			3	44b	258–260	256–258 (ref. 46)
9a	Furfural			3	48b	216–218	—
10a	H			2.5	15c	186–187	185–187 (ref. 47)
11a	4-OMe			2.5	12c	188–190	192–195 (ref. 48)
12a	4-Cl			3	46c	185–186	203–205 (ref. 49)
13a	4-F			3	19c	164–166	164–166 (ref. 50)
14a	4-Br			3	36c	183–185	186–188 (ref. 50)
15a	4-Me			3	31c	210–212	215–217 (ref. 49)
							231–233 (ref. 51)

^aReaction conditions: arylaldehyde (1 mmol), malononitrile (1 mmol), cyclohexanone/dimedone (1 mmol), ammonium acetate (1.5 mmol), ETG-acetamide (50 mg) at 80 °C.

^bIsolated yield by crystallization in ethanol (10–15 mL).

^cIsolated yield via column chromatography (n-hexane : EtOAc = 5 : 5).