K2CO3/Al2O3: An Efficient and Recyclable Catalyst for One-Pot, Three Components Synthesis of α-Aminophosphonates and Bioactivity Evaluation

Abstract

A simple and efficient method has been employed for synthesis of a novel series of biologically active α-aminophosphonates (4a-j) by reacting 1H-benzo[d]imidazole-2-carbaldehyde (1) and various aromatic amines (2a-j) and diethyl/dimethyl phosphite (3) by Kabachnik-Field's reaction in the presence of efficient heterogeneous K2CO3/Al2O3 catalyst under solvent-free conditions at 140 ºC. Structures of all the compounds were confirmed by 1H, 13C and 31P NMR and LC-MS. In addition to this antioxidant activity were also evaluated.

Relationship between Structure and Antibacterial Activity of α-Aminophosphonate Derivatives Obtained via Lipase-Catalyzed Kabachnik−Fields Reaction

“…The Kabachnik–Fields reaction is the most efficient method for the formation of carbon−phosphorus bonds using an aldehyde, amine, and H -phosphite. A number of other synthetic approaches have also been reported for the preparation of α-aminophosphonates [ 7 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 , 83 , 84 , 85 , 86 , 87 , 88 , 89 , 90 , 91 , 92 , 93 , 94 , 95 ]. These methods are generally conducted in the presence of various organic and inorganic bases [ 56 , 57 , ...…”

“…A number of other synthetic approaches have also been reported for the preparation of α-aminophosphonates [ 7 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 , 83 , 84 , 85 , 86 , 87 , 88 , 89 , 90 , 91 , 92 , 93 , 94 , 95 ]. These methods are generally conducted in the presence of various organic and inorganic bases [ 56 , 57 , 58 ] as well as Lewis and Bronsted acids, such as zirconium tetrachloride (ZrCl 4 ), aluminum chloride (AlCl 3 ), tan...…”

“…All microorganisms and media were accurately described in detail in the previous work [ 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 ] and analyzed by a Tukey test.…”