Lewis acid catalyst free synthesis of substituted imidazoles in 2,2,2-trifluoroethanol
摘要:
A simple, inexpensive, environmentally friendly, and efficient route for the synthesis of highly substituted imidazoles by the condensation of 1,2-dicarbonyl compounds, aldehydes, and ammonium acetate using 2,2,2-trifluoroethanol as a solvent is described. The solvent can be readily separated from reaction products and recovered in excellent purity for direct reuse.
A simple and efficient procedure for the preparation of silica-bonded propylpiperazine-N-sulfamic acid (SBPPSA) by the reaction of 3-piperazine-N-propylsilica (3-PNPS) and chlorosulfonic acid in chloroform is described. Silica-bonded propylpiperazine-N-sulfamic acid is employed as a recyclablecatalyst for the synthesis of highly substituted imidazoles from the reaction of benzil, aromatic aldehydes
Sulfuricacid ([3‐(3‐silicapropyl)sulfanyl]propyl]ester (SASPSPE) is used as a recyclable catalyst for the synthesis of 1,2,4,5‐tetrasubstituted imidazoles. A range of various polysubstituted imidazoles was synthesized via four‐component condensation of benzil, aldehydes, amines, and ammonium acetate in the presence of SASPSPE under solvent‐free conditions at 140°C. The heterogeneous catalyst was recycled
A new more atom-efficient multi-component approach for the synthesis of tetrasubstituted imidazoles via the one-pot condensation of nitriles, primary amines and benzoin has been described. Using this method, a wide...