Fabrication And Catalytic Properties Of Self-assembled Films Of ?-ketoimine-palladium (?) For Suzuki Coupling Reactions

Palladium-catalyzed carbon-carbon coupling is one of the important means in organic synthesis.However,in recent years,green chemistry has been paid more and more attention by environmental problems and energy crisis.Therefore,the development and research of high efficiency,recyclable,New catalysts with good stability become critical.The preparation of heterogeneous catalysts by selecting the appropriate method is a great challenge for the study of catalytic performance and catalytic mechanism of heterogeneous catalysts.In this paper,?-ketoimine-palladium(?)self-assembled monolayer(?-Ki-Pd)film and layer-by-layer Assembled multilayers of ?-ketoimine-palladium(?)([?-Ki-Pd]n)were prepared by self-assembly technique.?-Ki-Pd and [?-Ki-Pd]n was catalyzed by Suzuki-Miyaura coupling reaction.The prepared catalysts,as true heterogeneous catalysts were applied for catalyzing Suzuki coupling reaction.The main results are as follows: 1,?-ketoimine-palladium(?)self-assembled monolayer film(?-Ki-Pd)and layer-by-layer assembled multilayers of ?-ketoimine-palladium(?)([?-Ki-Pd]n)were successfully prepared by self-assembly technique and layer-by-layer self-assembly technique.The film catalysts were characterized by water-drop contact angle(WDCA),UV-Vis spectroscopy,Raman spectroscopy(RS),scanning electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS),and X-ray diffraction spectroscopy(XRD).2,The catalytic activity of layer-by-layer assembled multilayers of ?-ketoimine-palladium(?)([?-Ki-Pd]n)was higher than that of ?-ketoimine-palladium(?)self-assembled monolayer(?-Ki-Pd),due to the fact that the self-assembled multilayer films have more reactive sites than that of monolayers.Recycling and stability of [?-Ki-Pd]n are also better than ?-Ki-Pd,due to the cross-linking of the molecular chains of the multilayers.