KAl(SO4)2.12H2O Supported on Silica gel Catalyzed Coupling of 4- Hydroxyproline with Isatins, 11H-Indeno[1,2-b]quinoxalin-11-ones, Quinones and 9H-Fluoren-9-one: An Efficient Synthesis of Some Interesting Pyrroles

Some interesting pyrrole derivatives were synthesized in moderate to high yields by coupling of 4- hydroxyproline with isatins, 11H-indeno[1,2-b]quinoxalin-11-ones, quinones and 9H-fluoren-9-one, in the presence of catalytic amount of Alum supported on silica gel (Alum-SiO2), under microwave irradiation.