Multicomponent, one-pot synthesis and spectroscopic studies of 1-(2-(2,4,5-triphenyl-1H-imidazol-1-yl)ethyl)piperazine derivatives

Imidazole: Synthesis, Functionalization and Physicochemical Properties of a Privileged Structure in Medicinal Chemistry

“…In the presence of SO 4 2− /Y 2 O 3 as a catalyst, the multicomponent condensation of benzyl 56 , aminoethylpiperazine 59 , various aldehydes 60 and ammonium acetate in ethanol at 80 °C for 10 h was carried out to form tetrasubstituted 1,2,4,5-imidazole derivative 61 . The catalyst was reused up to five times with no significant loss in catalytic efficiency ( Figure 24 ) [ 43 ].…”

Click Synthesis of Novel 3‐(2‐(2,4,5‐Triphenyl‐1H‐imidazol‐1‐yl)ethyl)‐1H‐indoles Catalyzed by Glacial Acetic Acid and their Antibacterial Evaluation

“…Also, the imidazole nucleus is present as an essential structure in a number of therapeutic agents, fungicides, herbicides, [11] plant-growth regulators, [12] inhibitors of p38 MAP kinase, [13] and potent inhibitors of protein-protein interactions. [14] There are numerous methods reported for the synthesis of 1,2,4,5-tetrasubstituted imidazoles by four-component condensation of benzil with a variety of substituted aldehydes, primary amines and ammonium acetate using different catalysts such as sulphated yttria (SO 4 /Y 2 O 3 ), [15] L-Proline, [16] L-Cystein, [17] MCM-41, [18] p-TSA, [19] CAN, [20] Molecular Iodine, [21] Bronsted Acid Ionic Liquid, [22] DABCO, [23] Y(NO 3 ) × 6H 2 O, [24] (CuNO 3 ) 2 -Zeolite, [25] BF 3 ⋅ SiO 2, [26] Silica gel/NaHSO 4, [27] HCIO 4 -SiO 2, [28] ZrCl 4, [29] InCl 3 ⋅ 3H 2 O, [30] [31] Silica Sulphuric acid, [32] NiCl 2 ⋅ 6H 2 O/Al 2 O 3, [33] Yb(OTf) 3, [34] Selectflour TM , [35] H 2 SO 4 ⋅ SiO 2, [36] Ultrasonic Irradiation, [37] Amberlyst A-15, [38] PEG-400, [39] Glycerol, [40] and AcOH. [41] But, most of the above mentioned studies are associated with several disadvantages such as longer reaction time, using expensive catalysts, larger amount of catalyst, tedious work-up procedure, stringent reaction condition, lower selectivity and higher toxicity.…”

“…, entries[12][13][14][15][16]. Among these solvents, methanol gave excellent yield (98 %) of the target product within one minute.…”

Efficient synthesis of novel 1-hydroxy-2,4,5-trisubstituted imidazole derivatives via a one-pot, four-component reaction between hydroxylamine, benzonitriles, arylglyoxals and 1,3-dicarbonyl compounds

“…Over the past years, several successful methods have been reported for the preparation of 1-hydroxy imidazoles and related compounds. The mostly used methods are as follows: (a) condensations of αhydroxyimino ketones with N-methyleneamines; [14][15][16] (b) cyclocondensation of α-amino oxime derivatives with orthoesters; 17 (c) reaction of 1,2-diimines with oxime derivatives; 18 (d) condensation of α-hydroxyimino ketones with various methylidene alkylamines; 19 (e) three-component reaction of α-hydroxyimino ketones with a primary amine and aldehyde derivatives; 20 (f) via directed lithiation and metal-halogen exchange; 7 (g) [3+2] cycloaddition of oximino carbenoids with nitriles; 21 (h) three-component coupling between αhydroxyimino ketone, aldehydes and ammonium acetate; 2 (i) four-component reaction of benzil, aromatic aldehydes, an amine, and ammonium acetate; 22,23 (j) condensation of benzil, an aldehyde, and ammonium acetate in the presence of different catalysts; 24,25 and (k) one-pot [2+2+1] cycloannulation of 1,3bishet(aryl)monothio-1,3-diketones, α-substituted methylamines and sodium nitrite. 26 However, many of these methods have one or more disadvantages, such as the use of hazardous organic solvents, long reaction times, low yields, tedious work-up procedures, and use of expensive catalysts.…”