Ytterbium Triflate as an Efficient Catalyst for One‐Pot Synthesis of Substituted Imidazoles Through Three‐Component Condensation of Benzil, Aldehydes and Ammonium Acetate.

Abstract

Acetate. -Besides the catalyst, reaction temperature and solvent are also optimized and a probable mechanism is discussed. The process presented in the scheme is operationally simple, environmentally benign and the catalyst can be reused for at least three reaction cycles without loss of activity. -(WANG*, L.-M.; WANG, Y.-H.; TIAN, H.; YAO, Y.-F.; SHAO, J.-H.; LIU, B.; J.

A New Method for Synthesis of 2, 4, 5-Triaryl-1H-Imidazoles by Using L-Proline-NO3 (Ionic Liquid) as catalyst

“…. These have been reported in the literature on the synthesis of 2, 4, 5-trisubstituted imidazoles induced by zeolite HY [10], ionic liquids [11], itterbium triflate [12], silica-sulfuric acid [13]: Is part of the method. , InCl3 was catalyzed.…”

“…1 H NMR (400 MHz, DMSO-d6, δ ppm):12.37 (s, 1H, NH), 9.62 (s, 1H, OH), 7.87 (d, 2H, J = 8.4 Hz, Ar-H), 7.55 (d, 2H, J = 7.6 Hz, Ar-H), 7.66 (m, 10H, Ph), EIMS (m/z, %): 313 (M +1 ) Elemental analysis. C21H16N2O: C, 80.75; H, 5.16; N, 8.97.…”

Ce@STANPs/ZrO2 as Nanocatalyst for Multicomponent Synthesis of Isatin-Derived Imidazoles under Green Reaction Conditions

“…11 It is worthy to mention here that among the synthesized organic scaffolds, imidazoles are very important motifs in a number of organic molecules and have gained significant attention due to their varied biological and pharmacological activities, such as antiulcerative agent, 12 selective benzodiazepine receptor antagonist, 13 proton pump inhibitor, 14 platelet coagulation drug in animal and human beings 15 (Figure 1), antibacterial agent, 16 antitumor agent, 17 as pesticides, 18 CB 1 cannabinoid receptor antagonist, 19 modulators of P-glycoprotein-mediated multidrug resistance, 20 and as a glucagon receptor. 21 Various acidic and basic catalysts have been used in synthesizing substituted imidazoles (Figure 2) such as silica sulfuric acid, 22 acetic acid, 23 ZrCl 4 , 24 boric acid using ultrasound irradiation, 25 Yb(OTf) 3 , 26 potassium dihydrogen phosphate, 27 sodium bisulfite, 28 L-proline, 29 and nanozirconia. 30 The major drawbacks of most of these protocols are nonrecyclability of catalyst, use of reflux conditions, prolonged time period, use of expensive and toxic catalysts, high temperature, and low product yields.…”

An Efficient and Green Method for Synthesis of 2,4,5-Triarylimidazoles without Use of Any Solvent, Catalyst, or Solid Surface

“…Almost all of these methods use ammonium acetate as the ammonia source. Many of the reported methods require long reaction time and use of expensive catalysts and organic solvents [16][17][18][19][20][21][22][23]. The current literature shows that there has been a growing trend towards green synthesis of these compounds [24,25].…”