Facile and Efficient Synthesis of Tetrahydrobenzimidazo [2,1-]Quinazolin-1(2)-One Derivatives Using Brönsted Acidic Ionic Liquid Immobilized on Nanoporous Na-Montmorillonite.

In this work, an efficient and green procedure have been described for the synthesis of tetrahydrobenzimidazo[2,1-b]quinazolin-1(2H)-one derivatives using nanoporous sodium montmorillonite clay (Na+-MMT) modified with 1-methyl-3-(trimethoxysilylpropyl)-imidazolium hydrogen sulfate (Na+-MMT-[pmim]HSO4). The procedure gave the products in excellent yields in very short reaction times under solvent-free condition. Also this catalyst can be reused for six times without considerable loss of its catalytic activity.