Search results for "Solid-state"
showing 10 items of 530 documents
Isomerism and Ligand Rearrangement within the cyclo-P2S3 Middle Deck in Dimolybdenum Triple-Decker Complexes
2009
The molecular structure of [Cp*2Mo2P2S3] (1; Cp* = η5-C5Me5) has been reinvestigated. In DFT studies a series of various positional isomers A−E have been calculated for the model complex [(C5H5)2Mo2P2S3]. The energetically favored isomer [Cp*2Mo2(μ,η2:2-PS)2(μ-S)] (1B) reacts with W(CO)5THF to give [Cp*2Mo2P2S3·W(CO)5] (2). X-ray diffraction analysis of 2 confirms the presence of two η2:2-PS dumbbells and one singly bridging sulfur ligand, the W(CO)5 fragment being coordinated at one of the P atoms. Arrangement B is also found in the structure of the diadduct [Cp°2Mo2P2S3{W(CO)5}2] (3; Cp° = t-BuMe2C5H2), which is more stable than its Cp* analogue. 31P solid-state MAS NMR spectroscopic stud…
CH-Anion versus anion-π interactions in the crystal and in solution of pentafluorobenzyl phosphonium salts
2010
A series of phosphonium salts with pentafluorobenzyl substituents have been synthesized and were investigated in the crystal as well as in solution. The solid state structures of 1a, 1b and 2d reveal the presence of anion-π as well as CH-anion interactions. The two attractive, yet competitive forces seem to act in concert and a directing effect of the CH interaction on the relative position between anion and π-system is observed. The search for anion-π interactions in solution failed. Only CH-anion interactions proved to be important in solution.
Reactivity of Distibanes toward Trialkylalanes and -gallanes: Syntheses and X-ray Structures of Bisadducts and Heterocycles
2001
Reactions between distibanes of the type Sb2R4 and trialkylalanes and -gallanes R‘3M in 1:2 stoichiometry yield eight bisadducts of the type [Sb2R4][MR‘3]2 (R = Me, R‘ = t-Bu, M = Al 1, Ga 2; R = Et, M = Al, R‘ = Me 3, Et 4, t-Bu 5; M = Ga, R‘ = Me 6, Et 7, t-Bu 8), which were characterized by multinuclear NMR studies and elemental analysis. In addition, 1, 2, 5, and 8 are the first structurally characterized neutral main group Lewis acid−distibane bisadducts. 1−8 are unstable in solution toward the formation of heterocycles of the type [R2SbMR‘2]x. [Me2SbGa(t-Bu)2]3 (9) and [Et2SbGa(t-Bu)2]2 (10) have been isolated and their solid state structures determined by single-crystal X-ray diffrac…
Supramolecular stabilization of the phosphite-based polyoxomolybdate [Mo6(PO3)(HPO3)3O18]9−
2007
Abstract A novel phosphite-based hetero-polyoxomolybdate, [Mo 6 (PO 3 )(HPO 3 ) 3 O 18 ] 9− , has been isolated and structurally characterized. The most striking feature of this polyanion is the presence of peripheral phosphite groups linked to the MoO 6 octahedra. In the solid state, this cluster shows strong hydrogen bonding interactions that apparently play a key role in its stabilization and isolation from solution.
2003
Hydrogenolysis of the dialkyl complexes [Y(η5-C5Me4SiMe2R)(CH2SiMe3)2(THF)] (1a, R = Me; 1b, R = Ph) results in the formation of the tetranuclear dihydrido complexes [{(η5-C5Me4SiMe2R)Y}4(μ-H)4(μ3-H)4(THF)2] (2a, R = Me; 2b, R = Ph), characterized by NMR spectroscopy. 2a was studied by single crystal X-ray diffraction. In the solid state, an unsymmetrical tetrahedral configuration of four [Y(η5-C5Me4SiMe3)] units is observed, two of which contain each one molecule of THF. Each yttrium atom is bonded to two μ2- as well as three μ3-bridging hydrido ligands. Synthese und Charakterisierung eines vierkernigen Hydrid-Clusters von Yttrium [{η5-(C5Me4SiMe3)Y}4(μ-H)4(μ3-H)4(THF)2] Die Hydrogenolyse …
Conformation versus coordination: synthesis and structural investigations of tellurium(II) dithiolates derived from beta-donor-substituted thiols.
2002
New methods of preparing tellurium(II) dithiolates, Te(SR)(2), are presented. Te(SCH(2)CH(2)OAc)(2), 1, was made from Te(SCH(2)CH(2)OH)(2) by acetylation of the hydroxyl groups. Te(SCH(2)CH(2)SAc)(2), 2, [Te(SCH(2)CH(2)NH(3))(2)]Cl(2), 3, and Te(SC(6)H(4)(o-NH(2)))(2), 4, were synthesized by ligand exchange reactions of Te(S(t)Bu)(2) with 2 equiv of HSCH(2)CH(2)SAc, [HSCH(2)CH(2)NH(3)]Cl, and HSC(6)H(4)(o-NH(2)), respectively. Of all compounds, 4 exhibits the strongest thermal sensitivity toward decomposition and the largest low-field shift of the (125)Te NMR signal, two features that are attributed to weak Te.N interactions. The structural parameters of the CSTeSC unit exhibit very similar…
Untersuchungen zur Konformation von 2‐Diazo‐1,3‐diketonen
1988
Mit Hilfe von 1H- und 13C-NMR-Messungen in Losung (und im Festkorper) werden die Konformationen von 2-Diazo-1,3-diketonen (2a–f) mit sperrigen Resten untersucht. Investigation on the Conformation of 2-Diazo-1,3-diketones Conformational analyses of 2-diazo-1,3-diketones (2a–f) with bulky substituents are performed by applying 1H- and 13C-NMR measurements in solution (and in solid state).
Mononuclear lanthanide(III)-oxamate complexes as new photoluminescent field-induced single-molecule magnets: solid-state photophysical and magnetic p…
2020
Implementing additional optical (luminescent) properties into the well-known class of single-molecule magnets (SMMs) is considered as a promising route toward obtaining the next generation of optomagnetic materials for quantum information storage and computing. Herein, we report a joint optical and magneto-structural study for the two novel series of lanthanide(iii) complexes of general formula Bu4N[LnIII(HL)4(dmso)]·nH2O where H2L = N-(4-Xphenyl)oxamic acid with X = Cl and n = 2 [Ln = Eu (1_Cl), Gd (2_Cl), Dy (3_Cl), and Tb (4_Cl)] and X = F and n = 3 [Ln = Eu (1_F), Gd (2_F), Dy (3_F), and Tb (4_F)]. All these compounds are mononuclear species with each lanthanide(iii) cation in a low-sym…
Organometallic early lanthanide clusters: syntheses and X-ray structures of new monocyclopentadienyl complexes.
2004
The reaction of Ln(BH(4))(3)(THF)(3) or LnCl(3)(THF)(3) with 1 equiv of KCp*' ligand (Cp' = C(5)Me(4)n-Pr) afforded the new monocyclopentadienyl complexes Cp*'LnX(2)(THF)(n) (X = BH(4), Ln = Sm, n = 1, 1a, Ln = Nd, n = 2, 1b; X = Cl, Ln = Sm, n = 1, 3a) and [Cp*'LnX(2)](n') (X = BH(4), n' = 6, Ln = Sm, 2a, Ln = Nd, 2b; X = Cl, Ln = Nd, 4b). All these compounds were characterized by elemental analysis and (1)H NMR. Crystals of mixed borohydrido/chloro-bridged [Cp*'(6)Ln(6)(BH(4))(12-x))Cl(x)(THF)(n')] (x = 10, n' = 4, Ln = Sm, 2a', Ln = Nd, 2b'; x = 5, n = 2, Ln = Sm, 2a' ') were also isolated. Compounds 2a, 2b, 2a', 2b', and 2a'' were structurally characterized; they all exhibit a hexameric…
Solid‐State Anion–Guest Encapsulation by Metallosupramolecular Capsules Made from Two Tetranuclear Copper(II) Complexes (Eur. J. Inorg. Chem. 29/2007)
2007
The cover picture shows unique examples of homo- and heterochiral, dimeric metal capsules resulting from the self-assembly of two helical, bowl-shaped tetranuclear copper(II) complexes that encapsulate different anions in the solid state, like pearls in an oyster (shown as the background). This kind of self-assembled, coordination-bonded motifs are a major topic in metallosupramolecular chemistry because of their binding capabilities and associated host–guest chemistry. However, their magnetic properties are largely unexplored, and here we provide one of the rare magnetic studies on these host–guest systems. For more details on the combined structural and magnetic investigations of this cla…