Synthesis And Characterization Of Lanthanide Complexes (La/Gd) With Functionalized Aryloxide Ligands And Their Catalytic Behavior

In this thesis, a series of lanthanide/gadolinium complexes bearing functionalized aryloxideligands were designed and synthesized. The complexes obtained were characterized by elementalanalysis,1H NMR,13C NMR and X-ray single crystal diffraction. The catalytic properties of thecomplexes on the ring-opening polymerization of ε-caprolactone have been studied. The researchwork includes the following two parts:Part one: Synthesis and characterization of amine-bridged bis(phenolate) lanthenide complexesand their application as catalyst in the polymerization of ε-caprolactone.The amine-bridged bis(phenolate) ligands Et2NCH2CH2N(CH2-2-OH-C116H2-R-3-R2-5)2(H2L:R1=tBu, R2=tBu; H2L2: R1=tBu, R2=Me; H2L3: R1=Me, R2=Me) andCH3CH2CH2N(CH2-2-OH-C6H2-R1-3-R2-5)(H2L4: R1=tBu, R2=tBu; H2L5: R1=tBu, R2=Me;H612L: R=Me, R2=Me) were synthesized through Mannich reaction. A series of amine-bridgedbis(phenolate) lanthenide complexes2a-2l (LxLn[N(SiMe3)2](THF)y: Ln=La, Gd; x=1-6; y=0,1)and (L6)3Ln2(THF)(2m: Ln=La;2n: Ln=Gd) were synthesized by amine elimination reaction ofbis(phenolate) ligands with Ln[N(SiMe3)2]3(Ln=La, Gd). Complexe2e and2n were characterizedby X-ray single crystal analysis. The catalytic properties of complexes2a-2l on the ring-openingpolymerization of ε-caprolactone have been studied, and the mechanism for the formation of PCL wasalso studied and discussed.Part two: Synthesis and characterization of functionalized phenolate lanthenide complexes andtheir application as catalyst in the polymerization of ε-caprolactone.Schiff base ligands3,5-tBu2-2-OH-C6H2CH=N-R (R=p-CH3C6H4, p-BrC6H4, Cy, p-CH3OC6H4)were synthesized and a series of phenolate lanthanide complexes3a-3h((3,5-tBu2-2-O-C6H2CH=N-R)3Ln(THF)x: Ln=La, Gd; x=0,1) were synthesized by amineelimination reaction of phenolate ligands with Ln[N(SiMe3)2]3(Ln=La, Gd). Aminophenol ligand3,5-tBu2-2-OH-C6H2CH2NHC6H4-p-OCH3([HONH]) could be accessed by the reduction of Schiffbase3,5-tBu2-2-OH-C6H2CH=N-C6H4-p-OCH3. Lanthanide complexes {[ON]Ln[N(SiMe3)2]}(3i: Ln=La;3j: Ln=Gd) and [ON]3La2(3k: Ln=La;3l: Ln=Gd) were synthesized by amine eliminationreaction of Aminophenol ligand with Ln[N(SiMe3)2]3(Ln=La, Gd). The catalytic properties ofcomplexes3i-3l on the ring-opening polymerization of ε-caprolactone have been studied, and themechanism for the formation of PCL was also studied.