| Today phosphine ligands have been gradually replaced by nitrogen ligands in a variety of organic synthesis reactions. Imine ligands which includeα-diimine and Schiff base have been researched extensively and deeply. Suzuki coupling reaction and also has been a hotspot of synthetic chemistry. And so far, Researches on the catalytic system for Aryl fluoride are few. Our research focused on the palladium-catalyzed Suzuki cross-coupling reactions for Aryl fluoride supported byα-diimine ligands.These works were detailed as below:1. Synthesis ofα-diimine ligands and its complexesA series diimine ligands with different electronic property, rigidity and steric hindrance were prepared by condensation ofα,β-dione and alkyl substituted sulfanilic acid. Several Pd(II) and Ni(II) complexes of diimine were prepared. These ligands and complexes are all easily diffluent and stable in polar organic solvents, such as DMF, DMA and DMSO.α-Diimine ligand 6 was prepared by the condensation of 3,5-bis(trifluoromethyl)aniline and acenaphthenequinone. Palladium dichloride complex and mono-methylated palladium complex of ligand 6 were synthesized.2. Suzuki coupling of aryl fluoride catalyzed by diimine/Pd (II) systemsIn the third chapter we are mainly talking about Suzuki coupling reaction of aryl fluoride catalyzed by diimine/Pd (II) systems. Theα-diimine ligands were applied to the Suzuki coupling reaction of aryl fluoride which could be carried out in organic solvent. Low loading of palladium catalyst (2 mol %) were necessary for the coupling reaction. The coupling reaction could be smartly carried out at 100℃in organic solvent. The catalytic system has been found to tolerate several of functional groups.
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