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1.
Reaction of yttrium and lanthanum trichloride with 1 equiv of sodium or potassium hydrotris(3,5-dimethylpyrazolyl)borate and 1 equiv of 2,2'-bipyridine gives good yields of the complexes [MCl(2)(Tp(Me2))(C(10)H(8)N(2))] (M = Y (1), La (2)). The analogous compounds with 1,10-phenanthroline, [MCl(2)(Tp(Me2))(C(12)H(8)N(2))] (M = Y (3), La (4)), have been obtained by a similar procedure. The solid-state structures of 2-4 were determined by single-crystal X-ray diffraction and revealed that the compounds are all seven-coordinate with capped octahedral geometry. In contrast, reaction of yttrium trichloride with 1 equiv of sodium hydrotris(3,5-dimethylpyrazolyl)borate in the presence of 1 equiv of neocuproine affords [YCl(3)(Tp(Me2))][Na(neoc)(3))] (5). Compounds 1 and 2 provide an entry for the synthesis of complexes containing the bipyridyl ligand in a radical anionic form or in a dianionic form. Reaction of 1 and 2 with an excess of sodium amalgam gives [Y(Tp(Me2))(bipy)(THF)(2)] (6) and [La(Tp(Me2))(2)(bipy)] (7), respectively. The structures of both compounds have been determined by X-ray crystallography. Compound 7 can be oxidized with iodine to give [La(Tp(Me2))(2)(bipy)]I (8).  相似文献   
2.
The reaction of the cyclopentadienyllutetium anthracenide, C5H5Lu(C14H10)2−(THF)2 (1), with azobenzene yielded the [C5H5(THF)Lu(μ−η22−PhN—NPh)]2(THF)2 (2) binuclear complex. The structure of the reaction product was established by X-ray structural analysis. The dynamic behavior of complex2 in a THF-d8 solution was studied by1H NMR spectroscopy in the temperature range of 265–330 K. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1667–1671, September, 1997.  相似文献   
3.
The reaction of LuCl3(THF)3 with Na(1,3-Ph2C5H3) followed by the in situ reaction with Na2[Ph4C2] produced (1,3-Ph2C5H3)Lu(Ph4C2)(THF) (1). The structure of 1 was established by X-ray diffraction. In the crystal structure of 1, the bis-allyl η6-coordination of the tetraphenylethylene dianion to the lutetium cation was observed. The structures of (1,3-Ph2C5H3)LuCl2(THF)3 and (C5H5)LuCl2(THF)3 were determined by X-ray diffraction. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1912–1918, October, 2007.  相似文献   
4.
The random coefficient integer-valued autoregressive process was introduced by Zheng,Basawa,and Datta in 2007.In this paper we study the asymptotic behavior of this model(in particular,weak limits of extreme values and the growth rate of partial sums) in the case where the additive term in the underlying random linear recursion belongs to the domain of attraction of a stable law.  相似文献   
5.
(1RS,2SR,3RS,4SR,5RS)‐2,4‐Dibenzoyl‐1,3,5‐triphenylcyclohexan‐1‐ol or (4‐hydroxy‐2,4,6‐triphenylcyclohexane‐1,3‐diyl)bis(phenylmethanone), C38H32O3, (1), is formed as a by‐product in the NaOH‐catalyzed synthesis of 1,3,5‐triphenylpentane‐1,5‐dione from acetophenone and benzaldehyde. Single crystals of the chloroform hemisolvate, C38H32O3·0.5CHCl3, were grown from chloroform. The structure has triclinic (P) symmetry. One diastereomer [as a pair of (1RS,2SR,3RS,4SR,5RS)‐enantiomers] of (1) has been found in the crystal structure and confirmed by NMR studies. The dichoromethane hemisolvate has been reported previously [Zhang et al. (2007). Acta Cryst. E 63 , o4652]. (1RS,2SR,3RS,4SR,5RS)‐2,4‐Dibenzoyl‐3,5‐bis(2‐methoxyphenyl)‐1‐phenylcyclohexan‐1‐ol or [4‐hydroxy‐2,6‐bis(2‐methoxyphenyl)‐4‐phenylcyclohexane‐1,3‐diyl]bis(phenylmethanone), C40H36O5, (2), is also formed as a by‐product, under the same conditions, from acetophenone and 2‐methoxybenzaldehyde. Crystals of (2) have been grown from chloroform. The structure has orthorhombic (Pca21) symmetry. A diastereomer of (2) possesses the same configuration as (1). In both structures, the cyclohexane ring adopts a chair conformation with all bulky groups (benzoyl, phenyl and 2‐methoxyphenyl) in equatorial positions. The molecules of (1) and (2) both display one intramolecular O—H...O hydrogen bond.  相似文献   
6.
Journal of Chemical Crystallography - The crystal structure of decakis(μ-chloro)-tetrakis(1,2,4-triphenylcyclopentadienyl)-hexakis(tetrahydrofuran)-di-potassium-tetra-neodymium(III)...  相似文献   
7.
Controlled hydrolysis of the terbium cyclopentadienyl complexes results in the formation of the heteroligand tetranuclear terbium complex [{Tb(η5-C5H5)}3{Tb(THF)3}(μ3-Cl)(μ2-Cl)64-O)] (I), the recrystallization of which from tetrahydrofuran (THF) gives solvatomorph I · 0.5THF (Ia). According to the X-ray structure analysis data (CIF files CCDC 1569329 (I) and 1569330 (Ia)), the complexes are tetrahedral with the μ4-bridging O2– anion at the center of the tetrahedron. The cyclopentadienyl ligand in complex I is shown to act as an “antenna” providing luminescence of the complex.  相似文献   
8.
The significant variety in the crystal structures of rare‐earth carboxylate complexes is due to both the large coordination numbers of the rare‐earth cations and the ability of the carboxylate anions to form several types of bridges between rare‐earth metal atoms. Therefore, these complexes are represented by mono‐, di‐ and polynuclear complexes, and by coordination polymers. The interaction of LnCl3(thf)x (Ln = Eu or Y; thf is tetrahydrofuran) with sodium or diethylammonium diphenylacetate in methanol followed by recrystallization from a DME/THF/hexane solvent mixture (DME is 1,2‐dimethoxyethane) leads to crystals of the non‐isomorphic dinuclear complexes tetrakis(μ‐2,2‐diphenylacetato)‐κ4O:O′;κ3O,O′:O′;κ3O:O,O′‐bis[(1,2‐dimethoxyethane‐κ2O,O′)(2,2‐diphenylacetato‐κ2O,O′)europium(III)], [Eu(C14H11O2)6(C4H10O2)2], (I), and tetrakis(μ‐2,2‐diphenylacetato)‐κ4O:O′;κ3O,O′:O′;κ3O:O,O′‐bis[(1,2‐dimethoxyethane‐κ2O,O′)(2,2‐diphenylacetato‐κ2O,O′)yttrium(III)], [Y(C14H11O2)6(C4H10O2)2], (II), possessing monoclinic (P21/c) symmetry. The [Ln(Ph2CHCOO)3(dme)]2 molecule (Ln = Eu or Y) lies on an inversion centre and exhibits three different coordination modes of the diphenylacetate ligands, namely bidentate κ2O,O′‐terminal, bidentate μ2‐κ1O1O′‐bridging and tridentate μ2‐κ1O2O,O′‐semibridging. The terminal and bridging ligands in (I) are disordered over two positions, with an occupancy ratio of 0.806 (2):0.194 (2). The interaction of EuCl3(thf)2 with Na[Ph3CCOO] in methanol followed by crystallization from hot methanol produces crystals of tetrakis(methanol‐κO)tris(2,2,2‐triphenylacetato)‐κ4O:O′;κO‐europium(III) methanol disolvate, [Eu(C19H15O2)3(CH3OH)4]·2CH3OH, (III)·2MeOH, with triclinic (P) symmetry. The molecule of (III) contains two O,O′‐bidentate and one O‐monodentate terminal triphenylacetate ligand. (III)·2MeOH possesses one intramolecular and four intermolecular hydrogen bonds, forming a [(III)·2MeOH]2 dimer with two bridging methanol molecules.  相似文献   
9.
Russian Journal of Coordination Chemistry - The use of dicyanamide and chelating phenanthroline ligands resulted in the synthesis of organometallic europium and neodymium coordination polymers...  相似文献   
10.
Russian Journal of Coordination Chemistry - The reactions of lanthanum and neodymium triphenylacetates with polydentate 6- and 18-membered N- and O-heterocyclic ligands give various types of...  相似文献   
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