Grindstone chemistry: protic ionic liquid-substrate tuned green synthesis of 1,2-disubstituted and 2-substituted benzimidazoles with outstanding selectivity
Swapan Majumdar, Nabyendu Pramanik, Mithun Chakraborty, Dilip K. Maiti
An environmentally benign and highly catalyst-substrate controlled synthesis of 1,2-disubstituted and 2-substituted benzimidazoles with outstanding selectivity has been developed through grinding a mixture ofo -phenylenediamines, suitable aldehydes and an imidazolium trifluoroacetate protic ionic liquid catalyst. The newly developed metal-free catalysis approach produced 1,2-disubstituted benzimidazoles from aromatic aldehydes bearing electron donating group, whereas aromatic aldehydes possessing electron withdrawing groups and aldehydes with 2-alkoxy substitution selectively furnished 2-substituted benzimidazoles and their chiral analogues. Low energy consumption, short reaction time and solvent-free synthesis make this methodology green, providing a useful contribution to the existing procedures available for the synthesis of benzimidazole derivatives.
An efficient and environmentally benign method for synthesis of 1,2-disubstituted and 2 substituted benzimidazoles has been described. Although previous methods are available in literature for synthesis of such compounds, the ease of operation, solvent-free...
Innovative, but better methods known
Summary:
An efficient and environmentally benign method for synthesis of 1,2-disubstituted and 2 substituted benzimidazoles has been described. Although previous methods are available in literature for synthesis of such compounds, the ease of operation, solvent-free...