Some different approaches have been developed in order to determine the most efficient preparation of bis-benzimidazoles 1a - f under solvent-free conditions. All of the selected methods are simple, avoiding heating with corrosive mineral acids. Heating of the reactants on a sand bath method appears to have higher efficiency.
An efficient and versatile synthesis of 2, 2'-(alkanediyl)-bis-1H-benzimidazoles employing aqueous fluoroboric acid as catalyst: density functional theory calculations and fluorescence studies
作者:Chhanda Mukhopadhyay、Sabari Ghosh、Ray J. Butcher
DOI:10.3998/ark.5550190.0011.908
日期:——
Alkanediyl)-bis-1H-benzimidazoles (simple and mixed) with variable methylene spacers were synthesized in excellent yields with aqueousfluoroboricacid (45%) (0.1 ml) as catalyst under solvent-free conditions. Their optimized structures were obtained using DFT calculations where it was seen that the s-trans orientation of the two imidazole rings was preferred for all types of bis-benzimidazole systems