tert-Alcohol-functionalized imidazolium ionic liquid: catalyst for mild nucleophilic substitution reactions at room temperature

Encouraged by a synergistic effect on nucleophilic fluorination, an imidazolium mesylate salt (1a) possessing two different solvent properties in one molecule-tert-alcohol and ionic liquid was utilized in various nucleophilic substitution reactions. By a comparison study with 1-n-butyl-3-methylimidazolium ionic liquids, 1a has proved to be a better phase transfer catalyst even under room temperature conditions. It was successfully applied to other nucleophilic substitution reactions such as fluorination, chlorination, bromination, iodination, acetoxylation, azidation, and cyanation.

Tertiary alcohol containing [mim-tOH][OMs] exhibited excellent phase transfer catalytic activity and good product yield compared to [bmim] salts.