o-Semiquinonato and o-iminosemiquinonato rhodium complexes. EPR study of the reactions in coordination sphere of rhodium.

The number of dicarbonyl-o-semiquinonato (o-iminosemiquinonato) rhodium complexes was isolated and characterized. Some reactions of these compounds with tertiary phosphines (substitution, addition) were studied by EPR in solution using o-semiquinones (o-iminosemiquinones) as spin labels.

Synthesis and molecular structure of indium complexes based on 3,6-di-tert-butyl-o-benzoquinone. Looking for indium(I) o-semiquinolate.

The interaction of 3,6-di-tert-butyl-o-benzoquinone (3,6-Q) with indium in toluene leads to the tris-o-semiquinolate derivative (3,6-SQ)(3)In (3,6-SQ - radical-anion of 3,6-Q). According to single-crystal X-ray diffraction analysis, this complex has a trigonal prismatic structure. Magnetic measurements revealed that the exchange interactions between odd electrons of the paramagnetic ligands in (3,6-SQ)(3)In are antiferromagnetic in character.

Novel PEG-organized biocompatible fluorescent nanoparticles doped with an ytterbium cyanoporphyrazine complex for biophotonic applications.

The preparation and properties are described of two types of novel PEG-organized nanoparticles including silica-modified uniform disk-shaped nanoparticles doped with a fluorescent ytterbium cyanoporphyrazine complex; a large enhancement of red emission for both types of nanoparticles is observed in physiological liquids owing to their binding to biomolecules.

Chemistry of the phosphorus-nitrogen ligands. Multiple isomeric transformations of the diphosphinohydrazine bearing 8-quinolyl substituent: P→C, P→N, and P→P migrations caused by different factors.

The reaction of 8-quinolylhydrazine with 2 equiv of Ph(2)PCl in the presence of Et(3)N gives 8-[(Ph(2)P)(2)NNH]-Quin (1) (Quin = quinolyl) in 84% yield. The heating of 1 at 130 °C for 1 h in toluene results in migration of the [Ph(2)PNPPh(2)] group to a carbon atom of the quinolyl fragment to form an isomer, 7-(Ph(2)P-N═PPh(2))-8-NH(2)-Quin (2). The same migration is caused by the addition of LiN(SiMe(3))(2) to 1.

Zero kinetic energy spectroscopy: mass-analyzed threshold ionization spectra of chromium sandwich complexes with alkylbenzenes, (η(6)-RPh)(2)Cr (R = Me, Et, i-Pr, t-Bu).

For over 25 years zero kinetic energy (ZEKE) spectroscopy has yielded a rich foundation of high-resolution results of molecular ions. This was based on the discovery in the late 60's of long-lived ion states throughout the ionization continuum of molecular ions. Here, an example is chosen from another fundamental system pioneered at this university.

Reversible addition of alkynes to gallium complex of chelating diamide ligand.

Different alkynes add reversibly to the gallium complex of the dpp-Bian dianion. The reactions proceed with addition of the alkynes across the Ga-N-C fragment resulting in carbon-carbon and carbon-gallium bonds. In the case of 3 and 4 a full elimination of the alkyne takes place at T < 100 degrees C, whereas with adducts 5 and 6 it occurs at heating to ca.

Reduction of digallane [(dpp-bian)Ga-Ga(dpp-bian)] with Group 1 and 2 metals.

The reduction of digallane [(dpp-bian)Ga-Ga(dpp-bian)] (1) (dpp-bian=1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene) with lithium and sodium in diethyl ether, or with potassium in THF affords compounds featuring the direct alkali metal-gallium bonds, [(dpp-bian)Ga-Li(Et(2)O)(3)] (2), [(dpp-bian)Ga-Na(Et(2)O)(3)] (3), and [(dpp-bian)Ga-K(thf)(5)] (7), respectively. Crystallization of 3 from DME produces compound [(dpp-bian)Ga-Na(dme)(2)] (4). Dissolution of 3 in THF and subsequent crystallization from diethyl ether gives [(dpp-bian)Ga-Na(thf)(3)(Et(2)O)] (5).

Synthesis, structures, and electroluminescent properties of scandium N,O-chelated complexes toward near-white organic light-emitting diodes.

Three members of a new class of electroluminescent, neutral, and monomeric scandium N,O-chelate complexes, namely, Sc(III)-tris-2-(2-benzoimidazol-2-yl)phenolate (1), Sc(III)-tris-2-(2-benzoxyazol-2-yl)phenolate (2), and Sc(III)-tris-2-(2-benzothiazol-2-yl)phenolate (3), have been prepared and X-ray characterized. DFT calculations have been performed. In contrast to the most frequently applied dual or multiple dopants in multilayer white OLED devices, all our simpler devices with the configuration of indium tin oxide/N,N'-bis(3-methylphenyl)-N,N'-diphenylbenzidine/neat scandium complex/Yb exhibit close to near-white emission with a blue hue (CIE(x,y) = 0.

New trends in design of electroluminescent rare earth metallo-complexes for OLEDs.

The metal-organic complexes of Sc, Y, La and lanthanides, which were tested as luminescent materials in organic light emitting diodes (OLEDs), are collected. The performances of the devices are given. Advantages and drawbacks of organic derivatives of rare earth metals as emissive materials are considered.

One- and two-electron-transfer reactions of (dpp-Bian)Sm(dme)3.

The reduction of 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene (dpp-Bian) with an excess of samarium in 1,2-dimethoxyethane (dme) affords the Sm(II) complex (dpp-Bian)Sm(dme)(3) (1). The reaction of 1 with 0.5 mol equiv of 1,2-dibromostilbene proceeds with the formation of the dimeric Sm(III) complex [(dpp-Bian)SmBr(dme)](2) (2).

Acenaphthene-1,2-diimine chromium complexes.

The reaction of (dpp-BIAN)Mg(THF)3 (1) with anhydrous CrCl3 in THF at 80 degrees C affords the mixed chromium-magnesium complex (dpp-BIAN)Cr(mu-Cl)3Mg(THF)3 (2). The treatment of 2 with 1,4-dioxane causes the elimination of MgCl2 and the formation of dimeric [(dpp-BIAN)Cr(mu-Cl)(THF)]2 (3). The reaction of (dpp-BIAN)Na2 with CrCl3 gives the chlorine-free compound [Na(THF)6][(dpp-BIAN)2Cr] (4).

Transition metal NMR chemical shifts and polarizability effect in organometallic complexes.

The literature data on substituent influence on the (51)V, (55)Mn, (57)Fe, (59)Co, (61)Ni, (95)Mo, (103)Rh, (183)W, (187)Os and (195)Pt NMR chemical shifts (delta) and on J (M, P; M = Mn, Fe, Mo, Rh, W, Os) coupling constants have been analyzed for 30 series of the organometallic complexes. It has been established for the first time that the delta and J values depend on the inductive, resonance and polarizability effects of substituents. The polarizability effect is caused by the partial charge on the central M atom.

1,2-Bis(imino)acenaphthene complexes of molybdenum and nickel.

Molybdenum hexacarbonyl reacts with 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene (, dpp-BIAN) and 1,2-bis[(trimethylsilyl)imino]acenaphthene (, tms-BIAN) in toluene to produce (dpp-BIAN)Mo(CO)(4) () and (tms-BIAN)Mo(CO)(4) (), respectively. The reaction of [CpNi(CO)](2) with yields (dpp-BIAN)NiCp (). Metathesis between Li(2)(tms-BIAN) and NiCl(2)(dppe) affords the Ni(0) complex (tms-BIAN)Ni(dppe) ().

The first structurally characterized metal (kappa(2)N,P)-phosphinohydrazides: the key to understanding the intramolecular rearrangement R2P-NR'-NR'-M --> R'N=PR2-NR'-M. Metalloderivatives of diisopropylphosphinohydrazines: synthesis and properties.

A number of novel phosphinohydrazines, iPr(2)P-NPh-NPh-H (1), iPr(2)P-NH-NH-PiPr(2) (2), iPr(2)P-NMe-NH-PiPr(2) (3), and H-NMe-NH-PiPr(2) (4), were prepared and characterized. The interaction of 1 with 1 equiv of n-BuLi afforded a complex compound [Li(DME)(3)][Li{(NPh-NPh-PiPr(2))-kappaN}(2)] (5). The reaction of 5 with NiBr(2) resulted in the formation of the first stable transition metal phosphinohydrazide [Ni{(NPh-NPh-PiPr(2))-kappa(2)N,P}(2)] (6).

Yttrium complexes supported by linked bis(amide) ligand: synthesis, structure, and catalytic activity in the ring-opening polymerization of cyclic esters.

A series of new yttrium complexes supported by the bulky enediamido dianionic ligand DAB(2-) (DAB(2-) = (2,6-C(6)H(3)iPr(2))NC(Me)=C(Me)N(2,6-C(6)H(3)iPr(2))(2-)), that is, {DAB}Y(THF)(2)(mu-Cl)(2)Li(THF)(2) (1), {DAB}Y(OtBu)(THF)(DME) (2), and {{DAB}Y(BH(4))(2)}{Li(DME)(3)} (3), was synthesized by salt metathesis. The complexes were isolated after recrystallization in 73, 66, and 52% yield, respectively, and characterized in solution by NMR and in the solid state by single-crystal X-ray diffraction studies. In complex 1, the DAB(2-) ligand is bonded to the metal center via two covalent YN bonds, while in complexes 2 and 3 additional eta(2)-coordination of the C=C bond to the metal atom is observed, both in solution and in the solid state.

Redox isomerism in the lanthanide complex [(dpp-Bian)Yb(DME)(mu-Br)]2 (dpp-Bian = 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene).

Ytterbium reacts with 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene (1, dpp-Bian) in 1,2-dimethoxyethane (DME) to give complex (dpp-Bian)Yb(DME)(2) (2). Oxidation of 2 with an 0.5 mol equivalent of dibromostilbene affords dimeric compound [(dpp-Bian)Yb(DME)(mu-Br)](2) (3).

First structurally characterized mixed-halogen nickel(III) NCN-pincer complex.

A square-pyramidal mixed-halogen nickel(III) NCN-pincer complex (PipeNCN)NiClBr (where PipeNCN=2,6-bis(piperidinomethyl)phenyl) was structurally characterized. Bromine occupies apical position; pincer ligand and chlorine atom are in the basal plane. EPR detects that complex in solution exists as a mixture of two structural isomers with bromine or chlorine atoms in the top of pyramid.

Oxidation by oxygen and sulfur of Tin(IV) derivatives containing a redox-active o-amidophenolate ligand.

Oxidation of tin(IV) o-amidophenolate complexes [Sn(ap)Ph(2)] (1) and [Sn(ap)Et(2)(thf)] (2) (ap=dianion of 4,6-di-tert-butyl-N-(2,6-diisopropylphenyl)-o-iminobenzoquinone (ImQ)) with molecular oxygen and sulfur in toluene solutions was investigated. The reaction of oxygen with 1 at room temperature forms a paramagnetic derivative [Sn(isq)(2)Ph(2)] (3) (isq=radical anion of ImQ) and diphenyltin(IV) oxide [{Ph(2)SnO}(n)]. Interaction of 1 with sulfur gives another monophenyl-substituted paramagnetic tin(IV) complex, [Sn(ap)(isq)Ph] (4), and the sulfide, [Ph(3)Sn](2)S.

o-Semiquinonic PCP-pincer nickel complexes with alkyl substituents: versatile coordination sphere dynamics.

o-Semiquinonic nickel pincer complexes (R2PCP)Ni(SQ) show a versatile coordination sphere dynamics via "swing" or "fan" oscillations depending on the steric properties of the phosphorus substituents.

Migratory insertion of the R2P group into a nitrogen-nitrogen bond - a novel type of rearrangement in phosphorus-nitrogen ligand chemistry. 3. The rearrangement of triphosphinohydrazide ligand -N(PPh2)-N(PPh2)2 to triphosphazenide anion {[(Ph2P-N]2PPh2}- in the coordination sphere of divalent cobalt and nickel.

Hydrazine dihydrochloride reacts with 3 equiv of Ph2PCl in tetrahydrofuran in the presence of triethylamine to give tris(diphenylphosphino)hydrazine (1) in 70% yield. Each nitrogen atom in 1 has a trigonal-planar environment according to X-ray analysis. Thermolysis of 1 at 130 degrees C results in the formation of two products: bis(diphenylphosphino)amine and octaphenylcyclotetraphosphazene.

N,N'-diisopropyl-N''-bis(trimethylsilyl)guanidinate ligand as a supporting coordination environment in yttrium chemistry. Synthesis, structure, and properties of complexes [(Me(3)Si)(2)NC(Ni-Pr)(2)]YCl(2)(THF)(2), [(Me(3)Si)(2)NC(Ni-Pr)(2)]Y(CH(2)SiMe(3))(2)(THF)(2), and [(Me(3)Si)(2)NC(Ni-Pr)(2)]Y[(mu-H)(mu-Et)(2)BEt](2)(THF).

The reaction of anhydrous YCl3 with an equimolar amount of lithium N,N'-diisopropyl-N' '-bis(trimethylsilyl)guanidinate, Li[(Me3Si)2NC(Ni-Pr)2], in tetrahydrofuran (THF) afforded the monomeric monoguanidinate dichloro complex {(Me3Si)2NC(Ni-Pr)2}YCl2(THF)2 (1). Alkylation of complex 1 with 2 equiv of LiCH2SiMe3 in hexane at 0 degrees C yielded the monomeric salt-free dialkyl complex {(Me3Si)2NC(Ni-Pr)2}Y(CH2SiMe3)2(THF)2 (2). The bis(triethylborohydride) complex [(Me3Si)2NC(Ni-Pr)2]Y[(mu-H)(mu-Et)2BEt]2(THF) (5) was prepared by the reaction of complex 1 with 2 equiv of LiBEt3H in a toluene-THF mixture at 0 degrees C.

[(dpp-bian)Ga-Ga(dpp-bian)] and [(dpp-bian)Zn-Ga(dpp-bian)]: synthesis, molecular structures, and DFT studies of these novel bimetallic molecular compounds.

1,2-Bis[(2,6-diisopropylphenyl)imino]acenaphthene) (dpp-bian) stabilizes gallium-gallium and zinc-gallium bonds (compounds 1-3). The compound [(dpp-bian)Ga-Ga(dpp-bian)] (2) was prepared by the reaction of GaCl3 with K3[dpp-bian] and the heterometallic [(dpp-bian)Zn-Ga(dpp-bian)] (3) was prepared by a simple one-pot reaction of [{(dpp-bian)ZnI}(2)] with GaCl3 and K4[dpp-bian]. In contrast to [(dpp-bian)Zn-Zn(dpp-bian)] (1) and 3, compound 2 is ESR silent, thus proving the dianionic character of both dpp-bian ligands.

Metal template assembly of highly functionalized octacyanoporphyrazine framework from TCNE structural units.

A new route to the octacyanoporphyrazine framework based on the interaction of metal sandwich pi-complexes with TCNE has been developed.