Chitosan Schiff Base Palladium Catalytic Properties Of Catalysts In The Heck Reaction,

In this paper, the recent progress about chitosan-supported noble metal catalysts and the catalysts used in Heck reaction were reviewed in detail. On this base, the chitosan Schiff base Palladium catalyst and SiO₂ supported chitosan Schiff-base Palladium catalyst were prepared and their catalytic performances in the Heck reaction were studied. 1 Preparation and characterization of chitosan Schiff-base Palladium catalystChitosan Schiff-base Palladium catalyst was synthesized from chitosan and salicylaldehyde via grafting to form chitosan Schiff-base, followed by coordination with Palladium chloride. Chitosan, chitosan-Schiff base and chitosan-Schiff base Palladium catalyst were characterized with IR, XPS, XRD, TG-DTA and fuorescence spectrophotometry. According to the results of analysis, two structure of chitosan Schiff-base Palladium catalyst was proposed.The probably structure of the CS-schiff-base Palladium catalyst2 Studies on catalytic performance of chitosan Schiff-base Palladium catalyst in Heckreaction(1) Catalytic performance about the reaction of iodobenzene and acrylamide to produce the cinnamamide catalyzed by chitosan Schiff-base Palladium catalyst Effects of different reaction conditions (molar ratio of iodobenzene and acrylamide, kind and amount of base, reaction temperature, reaction time, amount of catalyst, solvent) on yields were investigated. Under the optimal reaction conditions: 10mmol iodobenzene, the molar ratio of iodobenzene, acrylamide and tributylamine was 1:1.3:1.8, 0.1 g catalyst, 2 mL DMF, 110°C for 1 hours, 91.1% yield of cinnamamide can be achieved. By filtrating from the reaction mixture and washing with the solvent, the catalyst could be reused for 7 times without the loss of activity, the yield of the 7th was 87.5%. It can also catalyze the...