| We synthesized and characterized lanthanides amide complexes of (Y, Nd, Sm) supported by aryloxo-functional N-heterocyclic carbene, an bridged bisphenoxide complexe of lanthanide from the cleavage of aryloxo-functional N-heterocyclic carbenes and an ion-pairs complex supported by aryloxo-functional N-heterocyclic carbene precursor. The main results as fellows:1. The amide complex of samarium Li(THF)Sm(NiPr2)4 (1) was synthesized and characterized by the reaction of LiNiPr2 with SmCl3 in 4:1 molar ratio in THF and hexane,2 Reaction of aryloxo-functional N-heterocyclic carbene precursor [HO-4, 6-di-tBu-C6H2-2-CH2{CH(NCHCHN)iPr}]Cl (A) , Li(THF)Ln(NiPr2)4 (Ln= Y, Nd, Sm) and n-BuLi in 2:1:1 molar ratio in THF at -78℃for 10h, and at room temperature for 12h, gave the corresponding complexes [0-4, 6-di-tBu-C6H2-2-CH2-{C(NCHCHNiPr)}]2 LnNiPr2 (Ln=Y(2), Nd(3), Sm(4)). All complexes were fully characterized by IR, elemental analysis, X-ray diffraction, and by 1HNMR and 13CNMR in the case of Y.3. The catalytic activity of complexes 2, 3 and 4 for e-Caprolactone and L-lactide polymerization were examined. All the complexes can catalyse polymerization of e-Caprolactone and L-lactide, gave the polymers with rather broader molecular weight distribution.4. Reaction of NaOAr, SmCl3 and aryloxo-functional N-heterocyclic carbene precursor [HO-4, 6-di-tBu-C6H2-2-CH2{CH(NCHCHN)Me}]Cl (B) in 4:1:1 molar ratio in THF in one-pot hadn't afforded an anionic phenoxide complex of samarium (5) supported by a bridged bisphenoxo through the cleavage of aryloxo-functional N-heterocyclic carbenes. The complexes 5 was characterized by IR, elemental analysis, X-ray diffraction.5 Reaction of aryloxo-functional N-heterocyclic carbene precursor A with NdCl3 in 2:1 molar ratio in THF yielded an ion-pairs complex 6, The complex 6 was characterized by IR, elemental analysis, and X-ray diffraction. The further reaction of 6 with alkali (NaN(SiMe3)2, LiNipr2) were tried and no definite complexes were isolated.
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