Monofluorinated indolizines 4, benzo[d]indolizines 7 and 4H-pyrrolo[1,2-a]benzimidazoles 8 were synthesized in moderate yields by 1,3-dipolar reaction between fluorinated vinyl tosylates 2a and N-ylides of pyridinium, isoquinolinium and benzimidazolinium, generated in situ from their halides salts. When the same N-ylides were allowed to react with 2,3,3-trifluoro-1-propenyl tosylate 2b, the unexpected product formylated indolizines and their derivatives 9 were obtained. The reaction mechanism is also proposed.

The intermolecular additions of alkyl halides to per-(or poly)fluorophenyl aromatic aldimines using zinc as a single-electron-transfer radical initiator have been studied in aqueous media. The reaction proceeds well for imines with different substituents at room temperature under air atmosphere and the corresponding fluorine-containing amines and 1,2-diamines are obtained in poor to good yields. A tentative reaction mechanism is proposed.

A versatile compound, Me2Si(C9H7)(C2B10H11) can be conveniently converted into the monoanion [Me2Si(C9H6)(C2B10H11)]Na, the dianion [Me2Si(C9H6)(C2B10H10)]Na2, and the trianion [Me2Si(C9H6)(C2B10H11)]K3 by treatment with 1 equiv or excess amounts of NaH or K metal in THF, respectively. Reaction of LnCl3 with 1 equiv of [Me2Si(C9H6)(C2B10H11)]Na in THF gave dichloride complexes [η5-Me2Si(C9H6)(C2B10H11)]LnCl2(THF)3 (Ln) Nd (1), Er (2)). They can further react with another equivalent of [Me2Si(C9H6)(C2B10H11)]Na to afford monochloride complexes [η5-Me2Si(C9H6)(C2B10H11)]2LnCl(THF)2 (Ln) Ce (3), Nd (4), Sm (5), Er (6)), which can also be prepared by treatment of LnCl3 with 2 equiv of [Me2Si(C9H6)-(C2B10H11)]Na in THF. 4 reacts with excess NaH in THF to produce [Na(THF)6][{η5:σ-Me2-Si(C9H6)(C2B10H10)}2Nd] (7), which can also be prepared from the reaction of NdCl3 with 2 equiv of [Me2Si(C9H6)(C2B10H10)]Na2 in THF. Treatment of 2 with 2 equiv of K metal at room temperature yielded [η5:η6-Me2Si(C9H6)(C2B10H11)]Er(THF)2 (8). Reaction of 6 with 1 equiv of NaH afforded [{η5:σ-Me2Si(C9H6)(C2B10H10)}{η5-Me2Si(C9H6)(C2B10H11)}]Er(μ-Cl)-Na(THF)3 (9), which can also be prepared from the reaction of 2 with 1 equiv of [Me2Si-(C9H6)(C2B10H10)]Na2 in THF. Treatment of 9 with a mixture of 1 equiv of NaOH and excess NaH in THF generated the dinuclear complex [Na2(THF)11][{η5:σ-Me2Si(C9H6)(C2B10H10)}-{μ-η5:σ-(C9H6)SiMe2O}Er]2 (10). Treatment of Me2Si(C9H7)(C2B10H11) with excess NaH in THF under UV-light followed by reaction with 1 equiv of LnCl3 resulted in the isolation of unprecedented biscarborane compounds [LnCl2(THF)5][μ-CH-(closo-C2B10H11)-nido-CB10H11] (Ln) Er (11), Y (12)). All of these complexes were characterized by various spectroscopic and elemental analyses. The solid-state structures of 7 and 9-12 were confirmed by singlecrystal X-ray analyses.

Several new 13-vertex closo-metallacarboranes of rare earths incorporating nido-and arachno-carborane ligands have been prepared and structurally characterized. They represent a new class of metallacarboranes bearing a h7-carboranyl ligand recently discovered in our laboratory. This work indicates that the substituents on carborane cage carbons may affect the overall molecular structures of the resultant 13-vertex closo-metallacarborane complexes, but have little influence on the interactions between the central metal ion and nido- or arachno-carborane ligand.

Reaction of Me2Si(C5H5)Cl with 1 equiv of Li2C2B10H10 in toluene/ether at 0℃, after hydrolysis, gave Me2Si(C5H5)(C2B10H11) (1) in 79% isolated yield. 1 can be conveniently converted into the monoanion [Me2Si(C5H4)(C2B10H11)]Na (2), the dianion [Me2Si(C5H4)-(C2B10H10)]Li2 (3), and the trianion [Me2Si(C5H4)(C2B10H11)]K3 (4) by treatment with NaH, MeLi, and K metal in THF at room temperature, respectively. 2 reacted with 1 equiv of LnCl3 in THF to give [η5-Me2Si(C5H4)(C2B10H11)]LnCl2(THF)3 (Ln) Nd (5), Sm (6), Er (7), Yb (8)) in good yield. Treatment of LnCl3 with 2 equiv of 2 or reaction of [è5-Me2Si(C5H4)-(C2B10H11)]LnCl2(THF)3 with an equimolar amount of 2 in THF resulted in the isolation of [η5-Me2Si(C5H4)(C2B10H11)]2LnCl(THF)2 (Ln) Nd (9), Sm (10), Y (11), Gd (12), Yb (13)) in good yield. Interaction of 3 with LnCl3 in THF in a molar ratio of 1∶1 or 2∶1 or reaction of [η5-Me2Si(C5H4)(C2B10H11)]2LnCl(THF)2 with 2 equiv of MeLi in THF gave the same compounds [{η5:σ-Me2Si(C5H4)(C2B10H10)}2Ln][Li(THF)4] (Ln) Nd (14), Y (15), Er (16), Yb (17)). Treatment of NdCl3 with an equimolar amount of 4 in THF or reaction of [η5-Me2Si-(C5H4)(C2B10H11)]NdCl2(THF)3 with excess K metal in THF produced [η5:η6-Me2Si(C5H4)-(C2B10H11)]Nd(THF)2 (18). Under similar reaction conditions, however, interaction of LnCl3 (Ln) Sm, Yb) with 4 in THF afforded the organolanthanide(Ⅱ) compounds {[η5:η6-Me2Si-(C5H4)(C2B10H11)]LnII(THF)2}{K(THF)2} (Ln) Sm (20), Yb (21)). The Sm analogue of 18, [η5:η6-Me2Si(C5H4)(C2B10H11)]Sm(THF)2 (19), was prepared from an unprecedented redox reaction of SmI2 with 2 equiv of 2 in THF. Reaction of 19 with excess K metal in THF gave 20. Unlike the SmI2 case, interaction of YbI2 with 2 equiv of 2 in THF gave [η5-Me2Si(C5H4)-(C2B10H11)]2YbII(THF)2 (22). All of these compounds were characterized by various spectroscopic and elemental analyses. The solid-state structures of compounds 5, 8, 9, 10, 14, 15, 16, 17, 19, and 22 were confirmed by single-crystal X-ray analyses. The reaction mechanism of the formation of 19 is also proposed.

Reaction of Me2Si(C9H7)Cl with 1 equiv of Li2C2B10H10 gave, after hydrolysis, the new versatile ligand Me2Si(C9H7)(C2B10H11) (1). 1 can be conveniently converted into the monoanion [Me2Si(C9H6)(C2B10H11)]-(2) and the dianion [Me2Si(C9H6)(C2B10H10)]2-(3) by treatment with 1 equiv or excess amounts of NaH, respectively. Treatment of SmI2 with 2 in THF gave the unexpected redox product [η5:η6-Me2Si(C9H6)(C2B10H11)]Sm(THF)2 (4). Reaction of SmI2 with 1 equiv of 3 in THF, followed by reaction with 2, gave the unexpected C-H bond reduction product [{η5:σ-Me2Si(C9H6)(C2B10H10)}2Sm][Na(THF)6] (5). In contrast, reaction of YbI2 with 1 or 2 equiv of 2 afforded [{η5-Me2Si(C9H6)(C2B10H11)}Yb(σ-I)(THF)2]2 (6) or [η5-Me2Si(C9H6)(C2B10H11)]2Yb(THF)2 (7), respectively. Treatment of YbI2 with 1 equiv of 3 in THF gave [η5:σ-Me2Si(C9H6)(C2B10H10)]Yb(THF)3 (8), which is the first mixed-ligand organolanthanide(II) complex containing both Ln-C ð and ó bonds to be reported. 8 can also be prepared from the reaction of 6 with excess NaH in THF. Reaction of 8 with 1 equiv of 2 in THF yielded [η5-Me2Si(C9H6)(C2B10H11)]Yb(THF)[(μ-η5):σ-Me2Si(C9H6)(C2B10H10)]Na-(THF)3 (9), which can also be prepared by reaction of 7 with 1 equiv of NaH in THF. These new complexes have been fully characterized by 1H, 13C, and 11B NMR, IR spectroscopy, and elemental analyses. The molecular structures of 4, 5, 8, and 9 have been further confirmed by single-crystal X-ray analyses.

Summary: Reaction of Me2Si(C9H7)(C2B10H11) with 4 equiv of NaNH2 in dry THF, followed by treatment with 1 equiv of LnCl3, gave unprecedented tetranuclear clusters of the general formula [{(η5-μ2-C9H6SiMe2NH)-Ln}2(μ3-Cl)(THF)]2(í4-NH)âTHF (Ln) Gd (1), Er (2)) in moderate yield. Their molecular structures have been confirmed by single-crystal X-ray analyses, which represent the first organometallic clusters containing a central μ4-imido group.

Reaction of Me2Si(Me2NCH2CH2C9H6)Cl with 1 equiv of t-BuNHLi yielded Me2Si(Me2-NCH2CH2C9H6)(t-BuNH) (1). Treatment of Me2NCH2CH2C9H7 with 1 equiv of n-BuLi, followed by reaction with an excess of Me3SiCl, produced Me2NCH2CH2C9H6SiMe3 (2) in 9% yield. Interaction of YbCl3 with 3 equiv of (Me3Si)2NLi in THF, after workup, produced the tetracoordinate ytterbium(Ⅲ) amide [(Me3Si)2N]3YbⅢ　(μ-Cl)Li(THF)3 (3) in 85% yield. Treatment of 3 with 2 equiv of 1 gave the ytterbium(Ⅱ) complex [è5:è1-Me2Si(Me2NCH2-CH2C9H5)(t-BuNH)]2YbⅡ (4) in 58% yield via a reductive reaction. To get some insight into the reaction, several reactions were initiated to study the effects of the t-BuNH group, silyl group, and N,N-dimethylaminoethyl group of the indene compounds, effects of coordinate ClLi(THF)3 in 3, and temperature effect on the reductive reaction. Treatment of 3 with-equiv of 2 afforded (η5:η1-Me2NCH2CH2C9H5SiMe3)2YbII (5) in 52% yield. Interaction of 3 with 2 equiv of Me2NCH2CH2C9H7 produced a ytterbium(Ⅱ) complex (η5:η1-Me2NCH2-CH2C9H6)2YbⅡ (6) in 63% yield. Treatment of the ytterbium(Ⅲ) complex [(Me3Si)2N]3YbIII with 2 equiv of Me2NCH2CH2C9H7 also afforded the ytterbium(Ⅱ) complex (η5:η1-Me2NCH2-CH2C9H6)2YbII (6) in 62% yield, which provides an alternate method for the preparation of 6. Treatment of 3 with 2 equiv of indene(C9H8) produced the ytterbium(Ⅲ) complex (η5-C9H7)2YbIIIN(SiMe3)2 (7). Treatment of 3 with 1 equiv of 1,2-bis(indenyl)ethane also produced the ytterbium(Ⅲ) complex meso-[ethylenebis(è5-indenyl)ytterbiumⅢ bis(trimethylsily)amide ((EBI)YbIIIN(SiMe3)2) (8). All the compounds were fully characterized by spectroscopic methods and elemental analyses. Complexes 3, 4, 5, 6, and 8 were additionally characterized by a single-crystal X-ray diffraction study. The formation pathway for the ytterbium(Ⅱ) complexes is proposed. The study showed that ytterbuim(Ⅱ) complexes 4, 5, and 6 can function as single-component MMA polymerization catalysts with good activity.

New ether-functionalized carboranyl-indenyl hybrid ligands were prepared. They can prevent lanthanocene chlorides from ligand redistribution reactions and offer samarium(Ⅱ) complexes unusual reactivities. Treatment of Me2SiCl(C9H6CH2CH2OMe) with 1 equiv of Li2C2B10H10 in toluene/Et2O afforded the monolithium salt [Me2Si(C9H5CH2CH2OMe)-(C2B10H11)]Li(OEt2) (2). Interaction of 2 with 1 equiv of n-BuLi in Et2O produced the dilithium salt [Me2Si(C9H5CH2CH2OMe)(C2B10H10)]Li2(OEt2)2 (3). Reaction of 3 with 1 equiv of LnCl3 at room temperature gave the complex salts of general formula [{[è5:ó-Me2Si(C9H5CH2CH2-OMe)(C2B10H10)]Ln(THF)(μ-Cl)3Ln[η5:η1:η-e2Si(C9H5CH2CH2OMe)(C2B10H10)]}2{Li(THF)}]-[Li(THF)4] (Ln) Y (4), Yb (5)). Upon heating, 5 was converted into [η5:η1:η-Me2Si(C9H5-CH2CH2OMe)(C2B10H10)]Yb(THF)(μ-Cl)2Yb[η5:η1:η-Me2Si(C9H5CH2CH2OMe)(C2B10H10)] (6) by eliminating LiCl. Treatment of 4 or 5 with 2 equiv of group 1 metal amides gave organorare-earth amide complexes [è5:è1:ó-Me2Si(C9H5CH2CH2OMe)(C2B10H10)]Y(NHC6H3-2,5-tBu2)-(μ-Cl)Li(THF)3 (8) or [η5:η1:η-Me2Si(C9H5CH2CH2OMe)(C2B10H10)]Yb(NHC6H3-2,6-iPr2)(í-Cl)Li(THF)3 (9). An equimolar reaction of SmI2 with 3 in THF generated, after addition of LiCl, [{[è5:η-Me2Si(C9H5CH2CH2OMe)(C2B10H10)]2Sm}{Li(THF)}]n (10) and [{η5:η1:η6-Me2-Si(C9H5CH2CH2OMe)(C2B10H10)Sm}2(í-Cl)][Li(THF)4] (11). In sharp contrast, a less reactive YbI2 reacted with 3 in THF, producing only salt metathesis product [η5:η1:η-Me2Si(C9H5-CH2CH2OMe)(C2B10H10)]Yb(DME)(THF) (12). 12 reacted with 1 equiv of 3 to give the ionic complex {[(μ-η5:η2):η1:η-Me2Si(C9H5CH2CH2OMe)(C2B10H10)]2Yb}{Li(THF)2}2 (13). All complexes were characterized by various spectroscopic techniques and elemental analyses. The structures of 5, 6, and 8-13 were further confirmed by single-crystal X-ray analyses.

The interaction of methoxyethyl functionalized indene compounds (C9H6-1-R-3-CH2CH2OMe, R=t-BuNHSiMe(1), Me3Si (2), H (3)) with [(Me3Si)2N]3Ln(μ-Cl)Li(THF)3 (Ln=Yb (4), Eu (5)) produced a series of new ytterbium (Ⅱ) and europium (Ⅱ) complexes via tandem silylamine elimination/homolysis of the Ln-N (Ln=Yb, Eu) bond.Treatment of the lanthanide (Ⅱ) amides [(Me3Si)2N]3Ln(μ-Cl)Li(THF)3 (Ln=Yb (4), Eu (5) with 2 equiv. of 1, 2and 3, respectively, produced, after workup, the ytterbium (Ⅱ) complexes [η5:η1-Me2Si(MeOCH2CH2C9H5)(NHBu-t)]2-YbII (6), (η5:η1-MeOCH2CH2C9H5SiMe3)2YbII (7), (η5:η1-MeOCH2CH2C9H6)2YbII (8) and the correspondingeuropium (Ⅱ) complexes [η5:η1-Me2Si(MeOCH2CH2C9H5)(NHBu-t)]2EuII (9), (η5:η1-MeOCH2CH2C9H5SiMe3)2EuII (10) and (η5:η1-MeOCH2CH2C9H6)2EuII (11) in moderate to good yield. In contrast, interaction of the corresponding indene compounds 1, 2 or 3 with the lanthanide amides [(Me3Si)2N]3Ln (Ln = Yb, Eu) was not observed, while addition of 0.5 equiv. of anhydrous LiCl to the corresponding reaction mixture produced, after workup, the corresponding ytterbium (Ⅱ) or europium (Ⅱ) complexes. All the new compounds were fully characterized by spectroscopic and elemental analyses. The structures of complexes 7, 9 and 10 were determined by single-crystal X-ray analyses. The catalytic activity of all the ytterbium (Ⅱ) and europium (Ⅱ) complexes on MMA polymerization was examined. It was found that all the ytterbium (Ⅱ) and europium (Ⅱ) complexes can function as single-component MMA polymerization catalysts. The temperature, solvent and ligand effects on the catalytic activity were studied.