Table 1.

Comparative synthesis of 2-oxo-1,2-dihydropyridine-3-carbonitrile derivatives (13a–e) by microwave irradiation and thermal heating.

product	Ar	Time		Yieldc (%)		mp (°C)
		MWa (min)	Thb (h)	MWa	Thb
13a	2-C4H3S	20	17	77	44	>300
13b	4-OCH3C6H4	20	18	79	45	>300
13c	4-FC6H4	15	10	87	56	>300
13d	4-ClC6H4	17	15	82	63	>300
13e	4-BrC6H4	17	14	83	61	>300

^aThe reaction was carried out by microwave irradiation at 250 W and 150 °C;

^bThe reaction was carried out by thermal heating at 150 °C in oil bath;

^cIsolated yields.