Wasserstoffbrückenbindungen in zweikernigen μ-Hydroxobis[trichloroantimon(V)]-Komplexen mit Phosphatbzw. Phosphonatgruppen als überbrückende Liganden

Hydrogen Bonds in Binuclear μ-Hydroxo-bis[trichloroantimony(V)] Complexes with Phosphate or Phosphonate Groups as Bridging Ligands Benzylphosphonic acid monoalkylesters react with antimony(V) chloride and water to yield Cl₃SbO(OH)[(C₆H₅CH₂)RPO₂]SbCl₃ · H₂O ( 1 : R = OCH₃; 2 : R = OC₂H₅). With difluoro phosphoric acid only Cl₃SbO(OH)(F₂PO₂)SbCl₃ ( 3 ) can be isolated. The crystal and molecular structures of 1 to 3 were determined. 1 and 2 both crystallizing orthorhombic in the space group Pnma are hydroxonium salts H₃O⁺[Cl₃SbO₂((C₆H₅CH₂)RPO₂)SbCl₃]^–. Strong hydrogen bridges link cations and anions to chains. One of the hydrogen atoms of the cation makes a weak but important OH/π interaction to the para C atom of the benzyl group. In 3 (monoclinic, P2₁/n) the molecules are connected by hydrogen bridges to fourfold δ and helices λ. In solution there is a rapid intermolecular exchange of protons. IR and NMR data are communicated and briefly discussed.     

Molybdänhalogenidcluster mit sechs terminalen Alkoholatliganden: (C18H36N2O6Na)2[Mo6Cl8(OCH3)6] · 6CH3OH und (C18H36N2O6Na2)2[Mo6Cl8(OC6H5)6]

Molybdenum(II) Halide Clusters with six Alcoholate Ligands: (C₁₈H₃₆N₂O₆Na)₂[Mo₆Cl₈(OCH₃)₆] · 6CH₃OH and (C₁₈H₃₆N₂O₆Na)₂[Mo₆Cl₈(OC₆H₅)₆] . The reaction of Na₂[Mo₆Cl₈(OCH₃)₆] and 2,2,2-crypt yields (C₁₈H₃₆N₂O₆Na)₂[Mo₆Cl₈(OCH₃)₆] · 6 CH₃OH ( 1 ), which is converted to (C₁₈H₃₆N₂O₆Na)₂[Mo₆Cl₈(OC₆H₅)₆] ( 2 ) by metathesis with phenol. According to single crystal structure determinations ( 1 : P3 1c, a=14.613(3) Å, c=21.036(8) Å; 2 : P3 1c, a=15.624(1) Å, c=19.671(2) Å) the compounds contain anionic clusters [Mo₆Cl₈ⁱ(OR^a)₆]^2? ( 1 : d(Mo—Mo) 2.608(1) Å to 2.611(1) Å, d(Mo—Cl) 2.489(1) Å to 2.503(1) Å, d(Mo—O) 2.046(4) Å; 2 : d(Mo—Mo) 2.602(3) Å to 2.608(3) Å, d(Mo—Cl) 2.471(5) Å to 2.4992(5) Å, d(Mo—O) 2.091(14) Å). Electronic interactions of the halide cluster and the phenolate ligands in [Mo₆Cl₈(OC₆H₅)₆]^2? is investigated by means of UV/VIS spectroscopy and EHMO calculations.     

Rhenium-Komplexe von Sauerstoffchelatliganden: Ein Weg zu neuen Radiopharmaka?

Rhenium Complexes Stabilized by Tris-chelating Oxygen Ligands: Potential New Radiopharmaca? Ris-chelating oxygen ligands of the general formula L^? = [(C₅H₄R)Co{P(O)R′R″}₃]^? (R = COOCH₃, COOH and R′ = OCH₃; R = H and R′ = O(CH₂)₅COOCH₃, O(CH₂)₅COOH; R″ = OCH₃) have been synthesized. These ligands L^? and others of the same type have been used to prepare the rhenium oxo complexes [LReO₃] and [LReOX₂] (X = Cl, Br, I). In order to judge their use in radioimmunotherapy the corresponding complexes containing radioactive rhenium isotopes have also been synthesized. The rhenium(VII) as well as the diamagnetic rhenium(V) complexes are stable in air in the solid state as well as in organic solvents. They hydrolyze slowly in water to yield perrhenic acid. The X-ray structures of the sodium salt Na[(C₅H₄COOCH₃)Co{P(O)(OCH₃)₂}₃] and of the rhenium complex [LReOBr₂] (R = H, R′ = R″ = OCH₃) have been determined. The sodium salt crystallizes in trimeric units with the composition [(NaL)₃ · 3 H₂O]. Each sodium has a distorted octahedral oxygen coordination. In [LReOBr₂] the ReO₄Br₂ octahedron is only slightly distorted.     

Improved synthesis of cyclic and polymeric phosphazenes based on facile chlorine substitution with phenols promoted by cesium carbonate

In this report we describe a very convenient synthetic method for the preparation in high yields and purity of cyclic [N₃P₃(OCH₂CF₃)₆] and [N₃P₃(OC₆H₄R)₆] (R = Br, CN, CHO, COC₆H₅, COCH₃, H, OCH₃), and polymeric [NP(OC₆H₄R)₂]_n (R = Br, CHO, COC₆H₅, H, Bu^t) phosphazenes from the direct reaction of the trimer [N₃P₃Cl₆] or the high polymer [NPCl₂]_n and the alcohol HO CH₂CF₃ or the para-substituted phenols HO C₆H₄R, using Cs₂CO₃ as proton abstractor and acetone or tetrahydrofuran as solvent.     

Salze von Halogennophosphorsäuren. VII Darstellung und Eigenschaften von Siliciumdichlorphosphaten

Salts of Halogenophosphoric Acids. VII. Preparation and Properties of Silicon Dichlorophosphates By reaction of SiCl₄ or SiHCl₃ with dichlorophosphoric acid the compounds H[Si(PO₂Cl₂)₅] · C₂H₅OC₂H₅, H[Si(PO₂Cl₂)₅] or Si(PO₂Cl₂)₄ have been prepared, the composition of which depends on the solvents used. Some properties of these compounds are described and possible Constitutions are discussed.     

l-Hydroxo/Alkoxo-l-oxo-l-sulfonato-jO:jO'-bis[trichloroantimon(V)]Verbindungen. Zweikernige Antimon(V)-Komplexe mit Sulfonatgruppen als überbrückenden Liganden

l-Hydroxo/alkoxo-l-oxo-l-sulfonato-jO:jO'-bis[trichloroantimony(V)] Compounds. Binuclear Antimony(V) Complexes with Sulfonate Groups as bridging Ligands Sulfonic acids react with antimony(V) chloride and water and water/alcohol resp. dependent of the molar ratios yielding Cl₃SbO(OH)(O₂S(O)CH₃)SbCl₃ ( 1 ), Cl₃SbO(OH)· (O₂S(O)CF₃)SbCl₃ ( 3 ) the monohydrate Cl₃SbO(OH)· (O₂S(O)CH₃)SbCl₃·H₂O ( 2 ) and the compounds Cl₃SbO(OR')(O₂S(O)CF₃)SbCl₃ ( 4 : R'=CH₃; 5 : R'=C₂H₅) and Cl₃SbO(OCH₃)(O₂S(O)C₂H₅)SbCl₃ ( 6 ) resp. The crystal and molecular structures of 1 to 3 , 5 and 6 are determined. 1 and 3 are associated by hydrogen bonds to dimers and crystallize monoclinic ( 1 : P2₁/c; 3 : P2₁/n). 2 is a hydroxonium salt H₃O⁺[Cl₃SbO₂(O₂S(O)CH₃)SbCl₃]^– with strong hydrogen bonds between cations and anions and crystallizes triclinic (P1). 5 and 6 crystallize monoclinic ( 5 : P2₁/m; 6 : P2₁/c). In 1 and 3 to 6 there is an intramolecular reorientation or an intermolecular exchange of protons and R' groups in solution. The NMR spectra are discussed.     

New 1,1′-Ring-substituted Vanadocene Dichlorides. Crystal structures of [V(η5-C5H4SiMe3)2Cl2] and [V(η5-C5H5)2Cl2]

The 1,1′-ring-substituted vanadocene dichlorides [V(η⁵-C₅H₄R)₂Cl₂] (R = CMe₃, SiMe₃, SiEt₃) have been prepared from VCl₄ and the appropriate lithiated cyclopentadiene, C₅H₄RLi, in 1 : 2 ratios. All complexes were characterized by elemental microanalysis and IR spectroscopy. The crystal structures of [V(η⁵-C₅H₄SiMe₃)₂Cl₂] 3 and the parent compound [V(η⁵-C₅H₅)₂Cl₂] 1 have been determined by X-ray diffraction and are in accordance with expectations. Compound 1 crystallizes with two crystallographically independent molecules in its monoclinic unit cell. These two molecules are quite similar in their essential structural features. Compound 3 crystallizes in the triclinic space group P1 . The trimethylsilylcyclopentadienyl rings are bound in a staggered relative orientation.     

Complexation of the 2, 4, 6‐Triallyloxy‐1, 3, 5‐triazine with Copper(I,II) Chlorides. Syntheses and Crystal Structures of [CuCl2·2C3N3(OC3H5)3], [Cu7Cl8·2C3N3(OC3H5)3], and [Cu8Cl8·2C3N3(OC3H5)3]·2C2H5OH

Interaction of copper(II) chloride with 2, 4, 6‐triallyloxy‐1, 3, 5‐triazine leads to formation of copper(II) complex [CuCl₂·2C₃N₃(OC₃H₅)₃] ( I ). Electrochemical reduction of I produces the mixed‐valence Cu^{I, II} π, σ‐complex of [Cu₇Cl₈·2C₃N₃(OC₃H₅)₃] ( II ). Final reduction produces [Cu₈Cl₈·2C₃N₃(OC₃H₅)₃]·2C₂H₅OH copper(I) π‐complex ( III ). Low‐temperature X‐ray structure investigation of all three compounds has been performed: I : space group P1¯, a = 8.9565(6), b = 9.0114(6), c = 9.7291(7) Å, α = 64.873(7), β = 80.661(6), γ = 89.131(6)°, V = 700.2(2) ų, Z = 1, R = 0.0302 for 2893 reflections. II : space group P1¯, a = 11.698(2), b = 11.162(1), c = 8.106(1) Å, α = 93.635(9), β = 84.24(1), γ = 89.395(8)°, V = 962.0(5) ų, Z = 1, R = 0.0465 for 6111 reflections. III : space group P1¯, a = 8.7853(9), b = 10.3602(9), c = 12.851(1) Å, α = 99.351(8), β = 105.516(9), γ = 89.395(8), V = 1111.4(4) ų, Z = 1, R = 0.0454 for 4470 reflections. Structure of I contains isolated [CuCl₂·2C₃N₃(OC₃H₅)₃] units. The isolated fragment of I fulfils in the structure of II bridging function connecting two hexagonal prismatic‐like cores Cu₆Cl₆, whereas isolated Cu₆Cl₆(CuCl)₂ prismatic derivative appears in III . Coordination behaviour of the 2, 4, 6‐triallyloxy‐1, 3, 5‐triazine moiety is different in all the compounds. In I ligand moiety binds to the only copper(II) atom through the nitrogen atom of the triazine ring. In II ligand is coordinated to the Cu^II‐atom through the N atom and to two Cu^I ones through the two allylic groups. In III all allylic groups and nitrogen atom are coordinated by four metal centers. The presence of three allyl arms promotes an acting in II and III structures the bridging function of the ligand moiety. On the other hand, space separation of allyl groups enables a formation of large complicated inorganic clusters.     

Einige Reaktionen mit [Mo6Cl8]Cl4

Some Reactions with [Mo₆Cl₈]Cl₄ The reaction of [Mo₆Cl₈]Cl₄ with different chemical agents has been investigated: The methoxylation depends on the CH₃O^? concentration in CH₃OH. The reaction with HF leads to a partial fluorinated [Mo₆Cl₈] product. With NH₄F (NH₄)₂[Mo₆Cl₈]F₆ in formed, the hydrolysis of which leads to [Mo₆Cl₈]F₃(OH) · 2.5 H₂O. This compound can be decomposed thermically into [Mo₆Cl₈]O₂. [Mo₆Br₈]F₆^2? on hydrolysis leads to [Mo₆Br₈]F₃(OH) · 5 H₂O. With CsF Cs₂[Mo₆Cl₈]F₆ is formed, which by hydrolysis is transformed into [Mo₆Cl₈]F₃(OH) · 2.5 H₂O and possibly to [Mo₆Cl₈]F₄ · xH₂O(?). In reaction of [Mo₆Cl₈]Cl₄ with H₂SO₄ one gets [Mo₆Cl₈](SO₄)₂. Salts e. g. [(C₆H₅)₄As]₂[Mo₆Cl₈](OC₆F₅)₆ and adducts e. g. [Mo₆Cl₈](OC₆F₅)₄ · 2 HMPA are prepared. The compounds have been characterized by X-ray powder-diagramms and by IR-spectra.     

Darstellung,spektroskopische Untersuchungen und Kristallstruktur von [Cl4SbO2P(CH3)2]2

Preparation, Spectroscopic and Crystal Structure Investigations of [Cl₄SbO₂P(CH₃)₂]₂ [Cl₄SbO₂P(CH₃)₂]₂ was prepared from SbCl₅ and HOP(O)(CH₃)₂ in CH₂Cl₂. The compound crystallizes in the space group P2₁/n with two dimeric units per unit cell; the lattice constants are a = 875, b = 1306, c = 923 pm and β 97.1°. Structural investigation by X-ray diffraction methods showed the Sb atoms in the dimeric units to be linked by O? P? O-bridges of the dimethylphosphinate groups to Sb₂O₄P₂ eight-rings of approximate symmetry C_2h. The vibrational spectrum (i.r., Raman) and the n.m.r. spectra (³¹P, ¹H) consist with this structure.     

Reactions between Triethyl Phosphate and Metal Halides

Triethyl phosphate reacts with M(I), M(II) or M(III) halides at 100–250°C with formation of the following complexes: M[OOP(OC₂H₅)₂]₃, (M ? Al, Ga, In, Sc, Y, Dy, Ti, V, Cr, Fe); M[OOP(OC₂H₅)₂]₂, (M ? Fe, Cu); VO[OOP(OC₂H₅)₂]₂; Li[OOP(OC₂H₅)₂]; M₂[OOP(OC₂H₅)₂]₂ [OOP(OC₂H₅)? O? P(OC₂H₅)OO], (M ? Mn, Co, Ni); and M₃HP₂O₇ (M ? Rb, Cs). These complexes were characterized by means of their infrared and electronic spectra and magnetic susceptibilities.     

Some new results on the Fischer-Hafner synthesis of vanadium arenes

The biphasic liquid system formed in the Fisher-Hafner reduction of VCl₃ in toluene contains the [V(η⁶-MeC₆H₅)₂]⁺ cation which has been isolated in the solid state as the tetraphenylborato- (from aqueous solution) or as the [Al₂Cl₇]⁻, [Al₄O₂Cl₁₀]²⁻ and [catena-Al₄O₂Cl₉]⁻ salt (directly from the biphasic liquid system). The crystal structures of [V(η⁶-MeC₆H₅)₂]₂[Al₄O₂Cl₁₀] (2), and [V(η⁶-MeC₆H₅)₂][catena-Al₄O₂Cl₉] (3), have been solved representing the first structural report of the [V(η⁶-MeC₆H₅)₂]⁺ cation (compounds 2 and 3) and of the polymeric nonachlorodioxoaluminate anion [Al₄O₂Cl₉]⁻ (compound 3).     

A concise and versatile route to tetrahydro‐1‐benzazepines carrying [a]‐fused heterocyclic units: synthetic sequence and spectroscopic characterization,and the molecular and supramolecular structures of one intermediate and two products

A concise, efficient and versatile route from simple starting materials to tricyclic tetrahydro‐1‐benzazepines carrying [a]‐fused heterocyclic units is reported. Thus, the easily accessible methyl 2‐[(2‐allyl‐4‐chlorophenyl)amino]acetate, (I), was converted, via (2RS,4SR)‐7‐chloro‐2,3,4,5‐tetrahydro‐1,4‐epoxy‐1‐benzo[b]azepine‐2‐carboxylate, (II), to the key intermediate methyl (2RS,4SR)‐7‐chloro‐4‐hydroxy‐2,3,4,5‐tetrahydro‐1H‐benzo[b]azepine‐2‐carboxylate, (III). Chloroacetylation of (III) provided the two regioisomers methyl (2RS,4SR)‐7‐chloro‐1‐(2‐chloroacetyl)‐4‐hydroxy‐2,3,4,5‐tetrahydro‐1H‐benzo[b]azepine‐2‐carboxylate, (IVa), and methyl (2RS,4SR)‐7‐chloro‐4‐(2‐chloroacetoxy)‐2,3,4,5‐tetrahydro‐1H‐benzo[b]azepine‐2‐carboxylate, C₁₄H₁₅Cl₂NO₄, (IVb), as the major and minor products, respectively, and further reaction of (IVa) with aminoethanol gave the tricyclic target compound (4aRS,6SR)‐9‐chloro‐6‐hydroxy‐3‐(2‐hydroxyethyl)‐2,3,4a,5,6,7‐hexahydrobenzo[f]pyrazino[1,2‐a]azepine‐1,4‐dione, C₁₅H₁₇ClN₂O₄, (V). Reaction of ester (III) with hydrazine hydrate gave the corresponding carbohydrazide (VI), which, with trimethoxymethane, gave a second tricyclic target product, (4aRS,6SR)‐9‐chloro‐6‐hydroxy‐4a,5,6,7‐tetrahydrobenzo[f][1,2,4]triazino[4,5‐a]azepin‐4(3H)‐one, C₁₂H₁₂ClN₃O₂, (VII). Full spectroscopic characterization (IR, ¹H and ¹³C NMR, and mass spectrometry) is reported for each of compounds (I)–(III), (IVa), (IVb) and (V)–(VII), along with the molecular and supramolecular structures of (IVb), (V) and (VII). In each of (IVb), (V) and (VII), the azepine ring adopts a chair conformation and the six‐membered heterocyclic rings in (V) and (VII) adopt approximate boat forms. The molecules in (IVb), (V) and (VII) are linked, in each case, into complex hydrogen‐bonded sheets, but these sheets all contain a different range of hydrogen‐bond types: N—H…O, C—H…O, C—H…N and C—H…π(arene) in (IVb), multiple C—H…O hydrogen bonds in (V), and N—H…N, O—H…O, C—H…N, C—H…O and C—H…π(arene) in (VII).     

Molybdänhalogenidcluster mit zwei terminalen Alkoholatliganden: Synthese und Kristallstrukturen von (C18H36N2O6Na)2[Mo6Cl12(OCH3)2] und (C18H36N2O6Na)2[Mo6Cl12(OC15H11)2] · 2C4H6O3

Molybdenum(II) Halide Clusters with two Alcoholate Ligands: Syntheses and Crystal Structures of (C₁₈H₃₆N₂O₆Na)₂[Mo₆Cl₁₂(OCH₃)₂] and (C₁₈H₃₆N₂O₆Na)₂[Mo₆Cl₁₂(OC₁₅H₁₁)₂] · 2C₄H₆O₃ . Reaction of Mo₆Cl₁₂ with two equivalents of sodium methoxide in the presence of 2,2,2-crypt yields (C₁₈H₃₆N₂O₆Na)₂[Mo₆Cl₁₂(OCH₃)₂] ( 1 ), which can be converted to (C₁₈H₃₆N₂O₆Na)₂[Mo₆Cl₁₂(OC₁₅H₁₁)₂] · 2C₄H₆O₃ ( 2 ) by metathesis with 9-Anthracenemethanole in propylene carbonate. As confirmed by X-ray single crystal structure determination ( 1 : C2/m, a=25.513(8) Å, b=13.001(3) Å, c=10.128(3) Å, β=100.204(12)°; : C2/c, a=15.580(5) Å, b=22.337(5) Å, c=27.143(8) Å, β=98.756(10)°) the compounds contain anionic cluster units [Mo₆ClCl(OR^a)₂]^2? with two alcoholate ligands in terminal trans positions ( 1 : d(Mo—Mo) 2.597(2) Å to 2.610(2) Å, d(Mo—Clⁱ) 2.471(3) Å to 2.493(4) Å, d(Mo—Cl^a) 2.417(8) Å and 2.427(8) Å, d(Mo—O) 2.006(13) Å; 2 : d(Mo—Mo) 2.599(3) Å to 2.628(3), d(Mo—Clⁱ) 2.468(8) Å to 2.506(7) Å, d(Mo—Cl^a) 2.444(8) Å and 2.445(7) Å, d(Mo—O) 2.012(19) Å).     

Über Chalkogenolate. 178. Untersuchungen über Kupfer(I)-ethylxanthat

On Chalcogenolates. 178. Studies on Copper(I) Ethyl Xanthate Yellow Cu[S₂C? OC₂H₅] has been prepared by two different methods. In contrast to earlier observations it is not soluble in ethanolic solutions containing [S₂C? OC₂H₅]^? ions in excess. Cu[S₂C? OC₂H₅] reacts with CS₃^2? ions to form [Cu(CS₃)]^?. The compounds [(C₆H₅)₄E][Cu(CS₃)] with E = P, As have been isolated.     

Unusual products in the reactions of hexachlorocyclotriphosphazatriene with sodium aryloxides

Reactions of hexachlorocyclotriphosphazatriene, N₃P₃Cl₆ 1 , with sodium aryloxides have been studied. Compound 1 was found to react by the nucleophilic substitution pathway to yield monocyclophosphazenes [N₃P₃Cl₆(OC₆H₂Bu¹₃-2,4,6) 5 and N₃P₃Cl₄(OC₆H₂Me-4-Bu¹₂-2,6)₂ 6 ] and bi(cyclophosphazenes) ([Cl₅N₃P₃-P₃N₃Cl₄(OC₆H₃Bu¹₂-2,6)] 7 and [N₃P₃(OC₆H₃Bu¹₂-2,6)₅]₂ 8 ). The unusual bi(cyclophosphazenes) 7 and 8 are the first examples of two cyclotriphosphazene rings linked by a P(SINGLE BOND)P bond [2.193 (2) Å], which have been obtained by reacting 1 with ArONa. The structures of compounds 5–8 are ascertained by elemental analyses, ¹H-, ³¹P-¹³C-NMR, IR, and MS spectra. The molecular structure of monocyclic-phosphazene 5 was determined by X-ray diffraction techniques for further structural assignment. It crystallizes in the monoclinic space group P2₁/m with a = 6.144(2), b = 17.079(9), c = 13.181(9) Å, β = 92.79(7), and Z = 2, R = 0.074. Compound 5 is on a crystallographic mirror plane, and there is only a half molecule in the asymmetric unit. © 1996 John Wiley & Sons, Inc.     

Strukturuntersuchungen an SIVN3-Gruppierungen. IV [1-3]

N-chloralkyl-nitridochloro Complexes of Molybdenum (VI). [Cl₅MoN-R]⁻ with R = CCl₃, C₂Cl₅. Crystal Structure of (AsPh₄)₂[(MoOCl₄)₂CH₃CN] In the reaction of tetraphenyl arsonium chloride with the complexes Cl₃PO (Cl₄)-MoN R (R=CCl₃, C₂Cl₅) the POCl₃ is displaced by chloride and yields [Cl₅MoN R] ⁻. From the i.r. spectra a structure with six-coordinated molybdenum and a MoN triple bond can be deduced. By reaction with water in acetonitrile the molybdenum is reduced to Mo(V) and the nitride ligand is removed yielding (AsPh₄)₂[(MoOCl₄)₂CH₃CN]. The crystal structure of this compund was determined with X-ray diffraction data. In the tetragonal structure (space group P4/n) AsPh₄⁺ cations and two different anions were found: square pyramidal [MoOCl₄]⁻ and [MoOCl₄ · NCCH₃]⁻ in which the nitrile is bonded in trans position to the oxygen. The short Mo O distances of 165 pm indicate a strong π-bonding.     

Synthese von Oxovanadium(V)‐halogeno‐Komplexen der tripodalen Sauerstoffliganden LR— = [η5‐(C5H5)Co{PR2(O)}3]—, R = OMe,OEt

Syntheses of Oxovanadium(V) Halide Complexes Stabilized with Tripodal Oxygen Ligands L_R^— = [η⁵‐(C₅H₅)Co{PR₂(O)}₃]^—, R = OMe, OEt The sodium salts of the tripodal oxygen ligands L_R^— = [η⁵‐(C₅H₅)Co{PR₂(O)}₃]^— (R = OMe, OEt) react with the oxovanadium halides V(O)F₃ and V(O)Cl₃ to yield deep red compounds of the type [V(O)X₂L_R]. Halide exchange reactions with [V(O)Cl₂L_OMe] und [V(O)F₂L_OMe] aiming at the preparation of the analogous bromide complex [V(O)Br₂L_OMe] led to the isomer [VO(L_OMe)₂][V(O)Br₄]. The crystal structure of [V(O)Cl₂L_OMe] has been determined by single crystal x‐ray diffraction. The compound crystallizes in the monoclinic space group P2₁/n with a = 9.6332(8), b = 15.0312(11) and c = 15.3742(12)Å, β = 100.181(8)°. The coordination around vanadium is distorted octahedral.     

Models of surface-confined metallocene derivatives

The silsesquioxane [((C₆H₁₁)₇Si₇O₉)(OH)₃] (LH₃) was reacted with [M(C₅H₅)₂Cl₂] (M = Ti, Zr, Hf) and with [Ti(C₅H₅)Cl₃]. The reaction with [Ti(C₅H₅)Cl₃] produced [Ti(C₅H₅)L], whereas the reaction with [Ti(C₅H₅)₂Cl₂] produced a mixture of [Ti(C₅H₅)L]_n. (n = 1, 2) as determined by NMR spectroscopy. Only [Ti(C₅H₅)L] could be isolated from the mixture. The reaction with [M(C₅H₅)₂Cl₂] (M = Zr, Hf) produced oligomeric species which contained no cyclopentadienyl ligands and which were formulated as containing trimeric [M₃L₄Cl]⁻ anions on the basis of analytical and spectroscopic data.     

Bildung und reaktivität kationischer rhodiummethyl- trimethylphosphit-komplexes;eine weitere metall- organische variante der Michaelis—Arbuzov-reaktion

C₅H₅Rh(P(OCH₃)₃]₂ (I) reacts CH₃I and (CH₃)₃OBF₄ at low temperatures to give [C₅H₅RhCH₃{P(OCH₃)₃}₂]X (II: X = I; III: X = BF₄). Elimination of CH₃I from II yields the phosphonate complex C₅H₅RhCH₃[P(OCH₃)₃]- [P(O)(OCH₃)₂] (IV) which reacts with (CH₃)₃OBF₄ to give III.