Table 2: KOH-alumina (10 mol%) catalyzed solvent-free synthesis of substituted pyridazines under microwave (MW) irradiation.

EntrySubstrate 2 (R3)Substrate 1 R1/R2Product 4Time (min)Yield (%)aM.p. (°C)c

1R3 = C6H5R1 = R2 = C6H54a689182–184[21]
2R3 = 4-CH3C6H4R1 = R2 = C6H54b586160–162[21]
3R3 = 2-CH3OC6H4R1 = R2 = C6H54c1076137–139
4R3 = 4-CH3OC6H4R1 = R2 = C6H54d885b164–166[21]
5R3 = 4-BrC6H4R1 = R2 = C6H54e881147–149[21]
6R3 = 4-ClC6H4R1 = R2 = C6H54f676179–181[21]
7R3 = 4-NO2C6H4R1 = R2 = C6H54g673b164–166[21]
8R3 = 406427.fig.001R1 = R2 = C6H54h877b190–192[21]

aSolated yield. bPurified by column chromatography. cLiterature references.