Study On Organic Reactions Catalyzed By Acidic Ionic Liquid

Acidic ionic liquids have emerged as promising acid catalysts in replacement ofconventional homogeneous and heterogeneous acidic catalysts because they areflexible, nonvolatile, noncorrosive, low toxicity, immiscible with many organicsolvents, and reusability, it attracts more and more attention from chemists in theworld recently and becomes hot point in green chemisty.This thesis will introduce some research in acidic ionic liquids promoted somereactions as follow:1.We have synthesized2,4,5-triaryl-1H-imidazoles by three-componentcondensation of aldehyde, benzil, ammonium acetate under solvent-free conditionsand130℃using ionic liquid [Et₃NH][HSO₄] as catalyst with good to excellent yieldbetween89%to98%in40min to120min. the recovered catalyst can be resused atleast five additional times in subsequent reactions without a considerable decrease incatalytic activity.2.We have synthesized1,8-dioxo-octahydroxanthenes by condensation ofaldehyde and5,5-dimethyl-1,3-cyclohexanedione under solvent-free conditions and100℃using ionic liquid [Et₃NH][HSO₄] as catalyst with good to excellent yieldbetween45%to97%in20min to80min, and using ionic liquid [BPy][HSO₄] ascatalyst with good to excellent yield between63%to97%in10min to60min. therecovered catalyst [Et₃NH][HSO₄] can be resused at least six additional times insubsequent reactions without a considerable decrease in catalytic activity. therecovered catalyst [BPy][HSO₄]can be resused at least six additional times insubsequent reactions without a considerable decrease in catalytic activity.3.We have synthesized14-Phenyl-14H-dibenzo[a.j]xanthene by condensation ofaldehyde and2-naphthol under solvent-free conditions and120℃using ionic liquid[Et₃NH][HSO₄] as catalyst with good to excellent yield between54%to93%in20min to140min. the recovered catalyst can be resused at least six additional times insubsequent reactions without a considerable decrease in catalytic activity.4.We have synthesized amidoalkyl naphthols by three-component condensationof benzaldehyde,2-naphthol and benzamide under solvent-free conditions and120℃using ionic liquid [Et₃NH][HSO₄] as catalyst with good to excellent yieldbetween65%to96%in30min to80min. the recovered catalyst can be resused at leastfive additional times in subsequent reactions without a considerable decrease incatalytic activity.