The influence of triethylamine on the hydrodechlorination reactivity of chlorophenols over Raney Ni catalyst

The hydrodechlorination (HDCl) of 2,4-dichlorophenol (2,4-DCP), 2-chlorophenol (2-CP) and 4-chlorophenol (4-CP) over Raney Ni in liquid phase with triethylamine (Et3N) under mild conditions was studied. The results showed that Et3N together with solvents significantly affected the HDCl reactivity or selectivity, in which ortho-positioned Cl of chlorophenols (CPs) was easier to be dechlorinated in methanol (MeOH) and ethanol (EtOH), whereas para-positioned Cl was preferentially dechlorinated in water. Different species and action mechanisms of Et3N in water and organic solvents possibly affected the HDCl reactivity or selectivity of CPs over Raney Ni.

Graphical AbstractEt3N together with solvents significantly affected the HDCl reactivity or selectivity of 2,4-DCP, in which ortho-positioned Cl was easier to be dechlorinated in methanol (MeOH) and ethanol (EtOH), whereas para-positioned Cl was preferentially dechlorinated in water.Figure optionsDownload as PowerPoint slideResearch Highlights
► Solvent influenced the hydrodechlorination of chlorophenols.
► Et3N influenced the hydrodechlorination selectivity of chlorophenols.
► Ortho-positioned Cl was easier to be dechlorinated in organic solvents with Et3N.
► Et3N played different roles in different solvents.