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A series of bis(amido) complexes of rare earth metals {2-[Ph2P(O)]C6H4NC(tBu)N(2,6-Me2C6H3)}Ln(N(SiMe3)2)2, (Ln = Y (2), Nd (3), La (4)) was synthesized using the amine elimination reaction of Ln[N(SiMe3)2]3 (Ln = Y, Nd, La) and parent amidine 1 in THF, and the products were isolated in 60 (2), 61 (3) and 72% (4) yields, respectively. The X-ray studies revealed that complexes 2–4 are solvent-free and feature intramolecular coordination of the Ph2PO group to the Ln ion. Complexes 2–4 were investigated as precatalysts for isoprene polymerization. The ternary systems 2–4/borate/AlR3 (AlR3 = AliBu3, AliBu2H; borate = [Ph3C][B(C6F5)4], [PhNHMe2][B(C6F5)4]) were found to be active in isoprene polymerization and enable complete conversion of 1000 equivalents of monomer into polymer at 25 °C within 1–24 h affording polyisoprenes with polydispersities Mw/Mn = 1.12–9.46. The effect of the organoaluminium component and [Ln]/[AlR3] ratio on the catalytic activity and selectivity of the ternary catalytic systems was investigated. Complexes 2–4 proved to be efficient catalysts for the ring-opening polymerization of rac-lactide, which allow conversion of up to 500 equivalents of monomer into a polymer at room temperature within 30 min and afford atactic polylactides with high molecular weights and moderate molecular-weight distributions (1.29–2.12). Complexes 2–4 appear to be well-suited for achieving immortal polymerization of lactide, through the introduction of large amounts of isopropanol as a chain-transfer agent.

A synthetic approach to rare-earth amido complexes coordinated by an ansa bis(amidinate) ligand with a 1,8-naphthalene linker was developed and allowed for the synthesis of a series of complexes [1,8-C10H6{NC(tBu)N-2,6-Me2C6H3}2]LnN(SiMe3)2(THF)n (Ln = Y, n = 0 (2); Ln = Sm, n = 1 (3); Ln = Nd, n = 1 (4)) in reasonable yields. Complexes 2–4 initiate ring-opening polymerization (ROP) of rac-lactide and enable complete conversion of 100–250 equiv. of monomer within 60–90 min at 25 °C. The obtained polylactides feature atactic structures and moderate molecular-weight distributions (Mw/Mn = 1.30–2.12). The experimental Mn values of the obtained polymers are found to be significantly higher than the calculated ones due to a slow initiation stage. Effective immortal ROP of lactide with 3–5 equiv. of isopropanol per metal center was performed using complexes 2–4 as the catalysts. The systems 2–4/iPrOH exhibit higher activities in ROP and allow for complete conversion of 100–300 equiv. of rac-lactide to polymer within 30–60 min at 25 °C and provide a living polymerization mode and very narrow polydispersities (Mw/Mn = 1.13–1.27). Complexes 2–4 as well as related borohydrides [1,8-C10H6{NC(tBu)N-2,6-Me2C6H3}2]Ln(BH4)(μ-BH4)Li(THF)2 (Ln = Sm, Nd) catalyze hydrophosphonylation of aldehydes at room temperature with good reaction rates and hydrophosphonylation of benzylideneacetone at 65 °C.

Neutral bis(alkyl)-organolanthanide complexes supported by tridentate (N-,N,N) monoanionic 5-methylthiazole- or benzothiazole-amidopyridinate ligands have been prepared and completely characterized: (LThiaMe2)Ln(CH2SiMe3)2 [Ln = Lu3+ (3), Er3+ (7), Yb3+ (8)] and (LBnThMe2)Lu(CH2SiMe3)2 (5). Similarly to related Y3+ systems, the nature of the thiazole unit controls the ultimate catalyst stability in solution. In the diamagnetic Lu3+ complex 5, a progressive and complete rearrangement of its metal coordination sphere takes place through a metal-to-ligand alkyl migration with subsequent benzothiazole ring-opening and generation of the Lu3+ mono(alkyl)-arylthiolate species stabilized by a tetradentate (N-,N,N,S)- dianionic ligand. On the other hand, the 5-methylthiazole containing complexes 3, 7 and 8 showed no evidence of any ligand rearrangement. Complexes 3-8 have been tested as homogeneous catalysts in the isoprene (IP) polymerization, after activation with selected organoborates. Binary systems 3/TB and 7/TB [TB = tritylium tetrakis(pentafluorophenyl)borate] show the highest activity and living character toward the IP polymerization affording polymers with relatively high trans-1,4-selectivity (up to 76.4 %), moderate molecular weights (Mn up to 146 000 g/mol) and narrow polydispersities (Mw/Mn). Depending on the rare-earth ion of choice, a prevalent trans-1,4 (Lu3+, Er3+, Yb3+; up to 76.4 %) or a dominant 3,4 (Y3+; 92.7 %) polymer structure is observed. The influence of the ligand type, metal ion and activator(s) on the ultimate catalyst activity and selectivity are discussed.

Purpose and tasks: to establish new prognostic criteria of date of prolongation of pregnancy with premature discharge of amniotic fluid on the basis of performance monitoring of cell immunity of mother in the dynamics of observation and the child at the time of completion childbirth. Material and methods. A clinical and laboratory examination of 50 pregnant women, the pregnancy of women was complicated by premature rupture of membranes at 22-34 weeks of gestation. The control group consisted of 40 women with normal pregnancy with the same time of gestation. The traditional methods of clinical and laboratory examination were used to assess the status of pregnant women. The study of peripheral blood was performed with hematological analyzer BC- 3000+. Subpopulations of peripheral blood lymphocytes was studied by cytometry using monoclonal antibodies (apparatus «FAC SCalibur» company «BectonDickinson», USA). Results. The development of leukocytosis with absolute and relative lymphopenia, reduction of CD16+56+lymphocytes and CD19 B lymphocytes were revealed in pregnant women with premature rupture of membranes. The failure of proliferative activity CD3+4+ T-helper cells, the increase of level of CD3+8+ cytotoxic T lymphocytes were revealed at the time of onset of labor after the prolongation of pregnancy. Prolongation of pregnancy at patients with premature rupture of membranes combined with the development of leukocytosis in the fetus, as well as the mother in the same period of observation. At the same time, unlike the parent organism, activation of B-lymphocyte proliferation and humoral immunity at fetus were occurred.

A series of lanthanide monoborohydrido complexes {C6H4-1,2-[NC(R)NR′]2}Ln(BH4)(L)n (Ln = Y, Nd, Sm; R = tBu, Ph; R′ = 2,6-Me2C6H3, SiMe3; L = dme = dimethoxyethane, n = 1; L = thf, n = 2), in which lanthanides are coordinated by bulky ansa-bis(amidinato) ligand systems with a conformationally rigid o-phenylene linker ({C6H4-1,2-[NC(R)NR′]2}2–), were synthesized by the salt metathesis reactions of equimolar amounts of Ln(BH4)3(thf)3 and {C6H4-1,2-[NC(R)NR′]2}X2(thf)n (X = Li, Na) in thf. X-ray diffraction studies revealed that the complexes are monomeric. Depending on the denticity of the donor ligand (L = dme or thf), the terminal borohydrido ligand coordinated to the metal ion can be located in either an equatorial (L = thf) or an apical (L = dme) position. All complexes are efficient catalysts for the ring-opening polymerization of rac-lactide, which allows to convert up to 1000 equiv. of monomer into a polymer at room temperature within 10–150 min and affords atactic polylactides with high molecular weights and moderate molecular-weight distributions (1.28–2.16). Yttrium–borohydrido complexes coordinated by the {C6H4-1,2-[NC(tBu)N(2,6-Me2C6H3)]2}2– ligand system showed enhanced catalytic activity compared to that of the analogue complexes containing the {C6H4-1,2-[NC(Ph)NSiMe3]2}2– ligand. The obtained borohydrido complexes catalyze the hydrophosphonylation of benzaldehyde at room temperature with good reaction rates.

The complexes {(Me3Si)2NC(NPri)2}2LnOBut (Ln = Y (1), Lu (2)) initiate the bulk polymerization of racemic lactide (LA) at 130 °C. At the monomer: initiator molar ratio ([LA]: 1) equal to 1000: 1, the quantitative conversion of the monomer is achieved within 6 h. The resulting polymers are characterized by a rather narrow monomodal molecular weight distribution (M w/M n = 1.46–1.82) and molecular weights up to 33400 g mol−1. The molecular weights of the resulting polylactides measured by gel permeation chromatography are 3–11 times lower than the values calculated from the monomer: initiator ratio on the assumption of one growing polymer chain per catalytic center. The reaction of the in-situ prepared complex [(Me3Si)2NC(NPri)2]NdCl2 with 2 equiv. of PriOLi produced the 11-nuclear cluster [{(Me3Si)2NC(NPri)2}Nd]4(μ3-OPri)8Li7(μ2-Cl)3(μ3-Cl)2(μ4-Cl)2 (3), which was isolated in 62% yield. The structure of compound 3 was established by X-ray diffraction. Complex 3 initiates both the bulk and solution polymerization of rac-lactide. In the bulk polymerization at the molar ratio [LA]: [Nd] = 500: 1, the 89% conversion of the monomer was achieved within one hour. The polylactide thus synthesized has the molecular weight M n = 19720 g mol−1 and a rather narrow polydispersity M w/M n = 1.54.

The mass spectra of the antimony(v) o-amidophenolate complexes were obtained by electron ionization mass spectrometry. The most intense peak in the spectra of the most compounds is [M–SbR3–Alk]+. At the same time, the molecular ion peak for all compounds, except the complexes with alkyl substituents at the antimony atom, is characterized by low intensity.

A new tridentate amidine 2-[Ph2P(O)]C6H4NHC(tBu)[double bond, length as m-dash]N(2,6-Me2C6H3) (1) bearing a side chain pendant Ph2P[double bond, length as m-dash]O group was synthesized and proved to be a suitable ligand for coordination to rare-earths ions. Bis(alkyl) complexes {2-[Ph2P(O)]C6H4NC(tBu)N(2,6-Me2C6H3)}Ln(CH2SiMe3)2(THF)n (Ln = Y, n = 1 (3), Ln = Er, n = 1 (4), Ln = Lu, n = 0 (5)) were prepared using alkane elimination reactions of and Ln(CH2SiMe3)3(THF)2 (Ln = Y, Er, Lu) in hexane and were isolated in 50, 70 and 75% yields respectively. The X-ray studies revealed that complexes 2-5 feature intramolecular coordination of P[double bond, length as m-dash]O groups to metal ions. The lutetium complex 5 proved to be rather stable: at 20 °C its half-life time is 1155 h, while for the yttrium analogue the half-life time was found to be 63 h. Complexes 3-5 were evaluated as precatalysts for isoprene polymerization. The systems Ln/borate/AliBu3 (Ln = 3-5, borate = [PhNHMe2][B(C6F5)4], [Ph3C][B(C6F5)4]) turned out to be highly efficient in isoprene polymerization and enable complete conversion of 1000-10,000 equivalents of monomer into polymer at 20 °C within 0.5-2.5 h affording polyisoprenes with a very high content of 1,4-cis units (up to 96.6%) and from narrow (1.49) to moderate (3.54) polydispersities. A comparative study of catalytic performance of the related bis(alkyl) yttrium complexes supported by amidinate ligands of different denticities and structures [tBuC(N-2,6iPr2C6H4)2](-), [tBuC(N-2,6-iPr2C6H4)(N-2-MeOC6H4)](-) and {2-[Ph2P(O)]C6H4NC(tBu)N(2,6-Me2C6H3)}(-) demonstrated that the introduction of a pendant donor group (2-MeOC6H4 or Ph2P(O)) into a side chain of amidinate scaffolds results in a significant increase in catalytic activity. The amidinate ligand bearing a Ph2P(O)-group provides a high isoprene polymerization rate along with excellent control over regio- and stereoselectivities and allows us to obtain polyisoprenes with a reasonable molecular weight distribution.

The reactions of NdI2 (1) with aryl halides, PhX (X = Cl, Br, I), in THF afford benzene and a minor amount of biphenyl. Benzyl chloride under the same conditions yields 1,2-diphenylethane, toluene and PhCH2I due to Cl/I exchange. Alkyl halides C7H15Br and cyclo-C6H11Cl are reduced to the corresponding hydrocarbons. t-BuCl affords a mixture of isobutane/isobutylene. Chlorotrimethylsilane is converted into Me3SiH, hexamethyldisilane and Me3SiO(CH2)4CH3 in 10%, 8% and 31% yields respectively at room temperature but 1%, 2% and 88% yields at −60 °C. In benzene, the interaction of 1 with benzyl chloride proceeds at 80 °C to give diphenylmethane in 66% yield. Without solvent the same reaction leads to formation of the oligomers PhCH2(p-C6H4CH2)nC6H4CH2Cl. Heating 1 in benzene with n-BuCl or cyclo-C6H11Cl affords mono- and disubstituted products, RC6H5 and 1,4-R2C6H4. The n-Bu groups in the reaction transform into sec-Bu isomers. Iodobenzene, bromobenzene, Me3SiCH2Cl and Me3SiCl are inert towards 1 in benzene.

The new rigid bidentate nitrogen ligands 1, 2-bis[(2, 5-di-tert-butylphenyl)imino]acenaphthene (1) (dtb-BIAN) and 1, 2-bis[(2-biphenyl)imino]acenaphthene (2) (bph-BIAN) have been synthesized by condensation of 1, 2-acenaphthylenedione with 2, 5-di-tert-butylaniline and 2-aminobiphenyl, respectively. Reduction of 1 and 2 with magnesium and calcium results in the formation of the monomeric metal complexes [(dtb-BIAN)Mg(THF)2] (3), [(bph-BIAN)Mg(DME)2] (4), and [(bph-BIAN)Ca(THF)3] (5). Compounds 1 — 5 have been characterized by C/H analyses, IR, 1H NMR, and 13C NMR spectra, the structures of 2, 3, and 5 have been estimated by single crystal X-ray diffraction. Monomere Magnesium- und Calciumkomplexe mit 1, 2-Bis[(2, 5-di-tert-butylphenyl)imino]acenaphthen (dtb-BIAN) und 1, 2-Bis[(2-biphenyl)imino]acenaphthen (bph-BIAN) als starre, dianionische Liganden Die neuen, starren und zweizahnigen Stickstoffliganden 1, 2-Bis[(2, 5-di-tert-butylphenyl)imino]acenaphthen (1) (dtb-BIAN) und 1, 2-Bis[(2-biphenyl)imino]acenaphthen (2) (bph-BIAN) werden durch Kondensation von 1, 2-Acenaphthylendion mit 2, 5-Di-tert-butylanilin bzw. 2-Aminobiphenyl erhalten. Die Reduktion von 1 und 2 mit Magnesium oder Calcium verlauft unter Bildung der monomeren Erdalkalimetallkomplexe [(dtb-BIAN)Mg(THF)2] (3), [(bph-BIAN)Mg(DME)2] (4) und [(bph-BIAN)Ca(THF)3] (5). Die Verbindungen 1 — 5 wurden durch C/H-Analysen, IR-, 1H-NMR- und 13C-NMR-Spektren, die Verbindungen 2, 3 und 5 daruberhinaus durch Rontgenstrukturanalysen charakterisiert.

A monoanionic amido-imino ligand system [(2,6-iPr2C6H3)N=C(Me)C(=CH2)N(C6H3-2,6-iPr2)](-) was successfully employed for the synthesis of monomeric dichloro [(2,6-iPr2C6H3)N=C(Me)C(=CH2)N(C6H3-2,6-iPr2)]LnCl2(THF)2 (Ln = Y, 2Y; Lu, 2Lu) and bis(alkyl) [(2,6-iPr2C6H3)N=C(Me)C(=CH2)N(C6H3-2,6-iPr2)]Ln(CH2SiMe3)2(THF) (Ln = Y, 4Y; Lu, 4Lu) species of yttrium and lutetium. Dichloro complexes 2Y and 2Lu turned out to be unstable in aromatic solvents. The ligand symmetrization reaction in the case of 2Y affords the yttrium complex coordinated by dianionic [(2,6-iPr2C6H3)NC(=CH2)C(=CH2)N(C6H3-2,6-iPr2)](2-) ligand, (2,6-iPr2C6H3)N=C(Me)C(Me)=N(C6H3-2,6-iPr2) and YCl3. On the contrary, bis(alkyl) species 4Y and 4Lu are rather stable and do not undergo such a transformation or thermal decomposition. The treatment of complex 4Y with DME resulted in C-O bond cleavage and the formation of a dimeric methoxy-alkyl species {[(2,6-iPr2C6H3)N=C(Me)C(=CH2)N(C6H3-2,6-iPr2)]Y(CH2SiMe3)(μ-OMe)}2 (5). The ternary systems 4Ln/AliBu3/borate (borate = [HNMe2Ph][B(C6F5)4] and [CPh3][B(C6F5)4]; molar ratio 1 : 10 : 1) performed high catalytic activity in isoprene polymerization and ability to convert into polymer 1000-5000 equivalents of isoprene in 20-120 min with quantitative conversion. The obtained polyisoprenes possessed high molecular weights (2.9 × 10(4)-4.1 × 10(4)) and moderate polydispersities (2.14-3.52). Predominant 3,4-regioselectivity (up to 78%) was observed.