Wells-Dawson heteropolyacid supported on silica: a highly efficient catalyst for synthesis of 2,4,5-trisubstituted and 1,2,4,5-tetrasubstituted imidazoles.
Heteropolyacid H(6)P(2)W(18)O(62)·24H(2)O (WD) supported on silica (WD/SiO(2)) has been used as an effective catalytic system for the synthesis of various 1,2,4,5-tetrasubstituted imidazoles by four-component condensation of benzil, aldehydes, amines and ammonium acetate under solvent-free conditions. This approach can be useful for three-component synthesis of 2,4,5-trisubstituted imidazoles. The same reactions were repeated by using benzoin instead of benzil.
Karimi
Ali Reza
AR
Department of Chemistry, Arak University, Arak, 38156, Iran. a-karimi@araku.ac.ir
Alimohammadi
Zahra
Z
Amini
Mostafa M
MM
D000148:Acids, Noncarboxylic / Q000737:chemistry / Q000494:pharmacology*; D000447:Aldehydes / Q000138:chemical synthesis; D002384:Catalysis / Q000187:drug effects; D002626:Chemistry, Pharmaceutical / Q000379:methods; D004526:Efficiency; D007093:Imidazoles / Q000138:chemical synthesis* / Q000737:chemistry; D008954:Models, Biological; D015394:Molecular Structure; D011108:Polymers / Q000737:chemistry / Q000494:pharmacology*; D012822:Silicon Dioxide / Q000737:chemistry*; D012997:Solvents; D013055:Spectrophotometry, Infrared; D017973:Tungsten Compounds / Q000737:chemistry / Q000494:pharmacology*
D000148:Acids, Noncarboxylic; D000447:Aldehydes; D007093:Imidazoles; D011108:Polymers; D012997:Solvents; D017973:Tungsten Compounds; D012822:Silicon Dioxide