Synthesis And Application Of Heterocyclic Carbene Palladium Compounds

Two parts have included in this thesis. Fist, we studied the palladium heterocyclic carbene compound about synthesis, characterization, crastal structure and catalytic activity. Second, cyclometals (Pd, Ir) complexes were synthesized from2-(4-bromophenyl)-pyridine and their luminescent properties were investigated.1. Three new N-heterocyclic carbene (NHC)-phosphine palladium(II) complexes Pd(IMeO)PPh3I22, Pd(IMeO)P(C6H4-p-Me)3l23and Pd(IMeO)PCy3I24(IMeO=l,3-di-4-methoxyphenyl-imidazolin-2-ylidene) have been easily prepared from the reaction of the corresponding iodide-bridged NHC dimer with phosphine ligands in high yields. N-4,6-dimethyl-2-pyrimidinylimidazole6and its hydroxyethyl derivative7has been synthesized and characterized. We synthesized bis(N-heterocyclic carbene) palladium complexe from7and Pd(OAc)2, but the result was a bis(N-arylimidazole) palladium complex8was formated. Additionally, the analogous bis(N-methylimidazole) palladium complex9has also been synthesiszed by the above method. Theses complexes were charcterized by elemental analysis, IR,1H NMR, ESI-MS and single-crystal X-ray analysis. Based on our experience in palladium-catalyzed Suzuki reactions, the reaction was performed under nitrogen atmosphere in dioxane in the presence of CS2CO3as base at110℃for12h. Complexes2,3,4,8and9were found to be efficient catalysts for the Suzuki reaction. 2.2-(4-bromophenyl)-pyridin respectively reacted with Li2PdCl4and IrCl3to synthesize the cyclometalated[Pd(Ⅱ), Ir(Ⅲ)]cl-bridged dimmer. They reacted with acetyl acetone can give the cyclometalated [Pd(Ⅱ)、 Ir(Ⅲ)] complexes14,16. By using imidazole chloride salts and triphenylphosphine depolymerize cyclopalladated dimeric can get four new cyclopalladated compounds. Theses complexes were characterized by IR,1HNMR and single-crystal X-ray analysis. The complexes10-16show blue phosphorescence with structureless emission peaks at about454,458,463,454,462,468,472nm. ？？？...