Dmitrii M. Roitershtein

Polyphenylcyclopentadienyl complexes of rare earth elements

Reaction of LnCl3(thf)x (Ln = Y, La, Yb, Lu) with NaCpPhn (CpPhn = 1,3-Ph2C5H3, 1,2,4-Ph3C5H2, Ph4C5H) leads to formation of monocyclopentadienyl dichloride complexes Yb(Ph2C5H3)Cl2(thf)3 (1), Ln(Ph3C5H2)Cl2(thf)3 (Ln = Y (2), Lu (3)), La(Ph4C5H)Cl2(thf)3 (4). Molecular structures of 1, 2 and the polynuclear complex [(Ph3C5H2)3Lu4(Cl)7(O)(thf)3] (5), which is a partial hydrolysis product of 3, have been established by the X-ray method.

Reaction of cyclopentadienyllutetium anthracenide with azobenzene. Synthesis and molecular and crystal structure of the binuclear complex [C5H5(THF)Lu(μ−η2:η2−PhN—NPh)]2(THF)2 and its dynamic behavior in solution

The reaction of the cyclopentadienyllutetium anthracenide, C5H5Lu(C14H10)2−(THF)2 (1), with azobenzene yielded the [C5H5(THF)Lu(μ−η2:η2−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.

An efficient route for design of luminescent composite materials based on polyethylene containing europium dibenzoylmethanate

Luminescent composite materials based on linear polyethylene doped by a well dispersed tetrakis dibenzoylmethanate europium complex have been developed. The anion of the latter serves as an efficient light harvesting antenna and possesses the desired photophysical properties. The targeted modification of the Eu complex, namely introduction of a long hydrocarbon chain into the tetraalkylammonium cation [RNEt3]+, has ensured the compatibility of the complex with the polyethylene matrix. The [RNEt3]+ cation has been obtained by using long-chained 1-iodoalkanes synthesized via the Nd-catalyzed ethylene oligomerization process. The photophysical properties and the homogeneity of the obtained composites have been controlled by optical spectroscopy, luminescence intensity mapping as well as scanning electron microscopy.

Spontaneous Association of the Terbium Cyclopentadienyl Complexes under Controlled Hydrolysis

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)6(μ4-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.

(2R,3R)-1,4-Dioxa­spiro­[4.4]nonane-2,3-di­carb­oxy­lic and (2R,3R)-1,4-dioxa­spiro­[4.5]decane-2,3-di­carb­oxy­lic acids

The title compounds, (CH2)nC3H2O(COOH)2 (n = 4, 5), display intermolecular hydrogen bonding, forming a two-dimensional framework.

A structural study of (1RS,2SR,3RS,4SR,5RS)-2,4-dibenzoyl-1,3,5-triphenylcyclohexan-1-ol chloroform hemisolvate and (1RS,2SR,3RS,4SR,5RS)-2,4-dibenzoyl-1-phenyl-3,5-bis(2-methoxyphenyl)cyclohexan-1-ol.

(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 (P1) 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. E63, 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.