| In view of the fact that organolanthanide complexes containing N and S ligands are well known to play an important role in many reactions, in this dissertation, the first deals with the reactivity of organolanthanide amides towards some small molecules, including CS2, CO2 and PhNCS. The crystal structures of seven insertion products were determined by X-ray analysis. The second is concerned with the synthesis of five organolanthanide thiolate complexes, among which the structures of four complexes have been established by X-ray diffraction studies, including the reactions with PhNCS and the catalytic activity for the homopolymerization and copolymerization of 2,2-dimethyltrimethylene carbonate(DTC) and ?caprolactone.1. The insertion reactions of CS2 into the Ln-N bond of lanthanocene diphenylamide were firstly studied and the insertion products, viz., [(CH3C5H4)2Y( 2-S2CNPh2)]2 CH3C6H5 (1) and [(CHaCsH4)2Yb( 2-S2CNPh2)] (2) wereobtained. Both complexes 1 and 2 were characterized by elemental analysis, IR spectroscopy, 1H NMR spectroscopy, 13C NMR spectroscopy and single-crystal X-ray diffraction. Complex 1 has a dimeric structure, which has an interlinked tricycle formed via two bridged S atoms, while 2 exists as a monomer. The central metal Y in complex 1 is coordinated by two CH3C5H4 rings and three S atoms to give the formal coordination number of nine.2. Complexes [(CH3C5H4)2Ln(O2CNPh2)]2 CH3C6H5 (Ln=Y(3), Yb(4)), [(t-BuC5H4)2Yb(O2CNPh2)]2 (5), and [(t-BuC5H4)2Yb(O2CNC5H10)]2 (6) were obtained through the insertion reactions of C into the Ln-N bond of Cp'2 LnNR.2(THF) (Ln = Y, Yb), respectively. The four complexes have been identified as a dimer by X-ray crystal structure determination.3. The reactivity of (CHaC5H4)2YNPh2(THF) with PhNCS was first examined. Theinsertion product, {(CH3C5H4)2Y[ 2-SC(NPh2)NPh]}2 (7), was fully characterized. Complex 7 has a dimeric structure, in which two (CH3C5H4)2Y fragments connect with two [SC(SPh)NPh]- units.4. A novel complex {[Na(THF)3][(CH3C5H4)4Srn4(O)(SPh)7]} 0.5[(CH3C5H4)2Sm(SPh)(THF)]2 THF CH3C6H5(8) was obtained through the reaction of (CHsC5H4)3 Sm with PhSH in 1:2 molar ratio. X-ray determination indicates that complex 8 is composed by two different molecules, in which the polynuclear unit and the dinuclear unit exist in a 2:1 ratio.5. (RC5H4)3Sm reacted with equimolar of 2-mercapto-benzothiazole (HSBT) in THF at room temperature to give (RC5H4)2Sm(SBT)(THF)(R = CH3(9), t-Bu(10)), which were characterized by elemental analysis, IR and X-ray diffraction. The crystal structure analysis showed that in the complex 10, Sm3+ is coordinated by two t-Bu C5H4 groups, one oxygen atom of THF, one sulfur and one nitrogen atoms from the chelating benzothiazole-2-thiolate ligand to form a distorted trigonal-bipyramidal geometry, giving the central metal a formal coordination number of 9.6. Treatments of LnCb with three equivalents of NaSBT at room temperature afforded Ln(SBT)3(THF)2 (THFXLn = Sm(11), Tb(12)) in good yields. Both complexes were characterized by elemental analysis, IR spectroscopy, and X-ray diffraction. Their crystal structures reveal that both 11 and 12 are solvated complexes. The central metal is coordinated by three nitrogen, three sulfur and two oxygen atoms from the chelating benzothiazole-2-thiolate ligand to form a distorted twelve-hedral geometry, giving the central metal a formal coordination number of 8.7. The insertion reactions of [(CH3C5H4)2Ln(u-SPh)(THF)]2 with PhNCS in a 1:1 mole ratio in tetrahydrofuran(THF) solution were first studied, affording complex (CH3C5H4)2Ln[n2-SC(SPh)NPh](THF) (Ln = Nd (13), Sm (14)). Both complexes have a monomer structure. The central metal is coordinated by two CH3C5H4 rings, one THF and S, N atoms from SC(SPh)NPh ligand which was formed from SPh group to phenyl isothiocyanate moiety to form a distorted trigonal-bipyramidal geometry. The formalcoordination number of the central metal is 9.g. The bimet...
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