Synthesis,crystal structure,and NMR spectroscopy of a 1,3,2λ5,4λ5-oxathiadiphosphetane

From the crude product of the synthesis of the dithiadiphosphetane [RP(S)S]₂ (with R = 2,4,6-iPr₃C₆H₂), the trans-oxathiadiphosphetane has been isolated, C₃₀H₄₀OP₂S₃. X-ray structure analysis and mass spectroscopic investigations give unequivocal evidence for this structure: monoclinic, C2/c (no. 15), a = 13.066(8), b = 21.726(8), c = 12.070(6) Å, β = 103.54(10)°, V = 3331 ų, Z = 4, and D_c = 1.158 g/cm³. The asymmetric unit consists of half the formula unit. Solid-state ³¹P NMR spectra give information about the chemical shift anisotropy. Results of IGLO calculations of the ³¹P nuclear magnetic shielding tensor agree satisfactorily with the experimental data. Monitoring the reaction of several dithiadiphosphetanes with benzophenone in solution by ³¹P NMR spectroscopy indicates that additional oxathiadiphosphetanes as well as thiotrimetaphosphonates are present. © 1996 John Wiley & Sons, Inc.     

Synthesis, X-ray crystal structure and X-band EPR of [Cu(H(2)O)(2)(imH)(4)] x Sq single crystals

The copper salt [Cu(H(2)O)(2)(imH)(4)] x Sq has been synthesized at room temperature. Crystal structure of the [Cu(H(2)O)(2)(imH)(4)] x Sq (Sq is squarete dianion (C(4)O(4)(2-)) and imH is imidazole (C(3)H(4)N(2))) complexes has been investigated by single-crystal X-ray diffraction analyses and the environment of copper ion has been identified by EPR. The single crystal is triclinic with the space group P1. The unit cell dimensions of the crystals are a=9.317 Angstrom, b=9.958 Angstrom, c=12.130 Angstrom, alpha=69.99 degrees , beta=76.61 degrees and gamma=78.13 degrees . The unit cell contains two molecules. The Cu(II) atom has an octahedral arrangement in which the Cu(II) ion lies on the inversion canter and is coordinated by four imidazole ligands with the equatorial plane and two water molecules with the octahedral axial. The complex shows a normal magnetic moment and the single crystal EPR spectra consist of two sets of four hyperfine lines of copper. The ground wave function of the hole of the Cu(2+) is an admixture of d(x(2) - y(2)) and d(z(2)) states.     

Pentafluoro(aryl)‐λ6‐tellanes and Tetrafluoro(aryl)(trifluoromethyl)‐λ6‐tellanes: From SF5 to the TeF5 and TeF4CF3 Groups

The TeF₅ group is significantly underexplored as a highly fluorinated substituent on an organic framework, despite it being a larger congener of the acclaimed SF₅ group. In fact, only one aryl‐TeF₅ compound (phenyl‐TeF₅) has been reported to date, synthesized using XeF₂. Our recently developed mild TCICA/KF approach to oxidative fluorination provides an affordable and scalable alternative to XeF₂. Using this method, we report a scope of extensively characterized aryl‐TeF₅ compounds, along with the first SC‐XRD data on this compound class. The methodology was also extended to the synthesis and structural study of heretofore unknown aryl‐TeF₄CF₃ compounds. Additionally, preliminary reactivity studies unveiled some inconsistencies with previous literature regarding phenyl‐TeF₅. Although our studies conclude that the arene‐based TeF₅ (and TeF₄CF₃) group is not quite as robust as the SF₅ group, we find that the TeF₅ group is more stable than previously thought, thus opening a door to explore new applications of this motif.     

Syntheses,Structures and Electrochemistry Properties of Two Dicyanamide Manganese(III) Complexes [Mn(5‐Brsalen)(dca)]·CH3OH and [Mn(3‐Meosalphen)(dca)(H2O)]

Two manganese(III)‐dicyanamide compounds, [Mn(5‐Brsalen)(dca)] · CH₃OH ( 1 ) and [Mn(3‐Meosalphen)(dca)(H₂O)] ( 2 ) (dca = dicyanamide anion, [N(CN)₂]^–), were synthesized and characterized by elemental analysis, IR spectroscopy, single‐crystal X‐ray structure analysis, and cyclic voltammetry. The structure of complex 1 is an infinite zigzag chain of hexacoordinate Mn^III ions, in which the adjacent manganese atoms are connected by dca in μ_1,5‐bridging mode. The molecular structure of complex 2 consists of a hexacoordinate Mn^III atom, which generates a slightly distorted octahedral arrangement, and a dimer structure is formed by intermolecular hydrogen bonding interactions. The electrochemical properties of the two complexes were measured by cyclic voltammetry.     

Molekül- und Kristallstruktur von 9λ4-Thia-2,4,6,8,10,11-hexaza-1λ5,3λ5,5λ5,7λ5-tetraphosphabicylo[5.3.1]undeca-1,3,5,7(11),8,9-hexaen,einem schwefeldiimidoüberbrückten Cyclotetraphosphazen

Molecular and Crystal Structure of 9λ⁴-Thia-2,4,6,8,10,11-hexaaza-1λ⁵,3λ⁵,5λ⁵,7λ⁵-tetraphosphabicylo[5.3.1]undeca-1,3,5,7(11),8,9-hexaene, Cyclotetraphosphazene Bridged by a Sulfur Diimide Group We have carried out an X-ray structure analysis of the title compound ( 1 ). 1 crystallizes in the monoclinic space group P2₁/b with a = 9.436(4), b = 20.102(7), c = 11.622(5) Å, γ = 103.52(8)°, Z = 8. There are two molecules in the asymmetric unit, which in approximation can be transformed one into the other by additional symmetry elements of a substructure of a space group B2/b. The S = N bond lengths are 1.53 Å. The P? N bonds connecting the SN₂ system are 1.666 Å long. They are significantly longer than the P? N multible bonds in the P₄N₄ ring within a range of 1.517 to 1.565 Å. The sulfur diimide unit and its substituents are coplanar causing a half-boat conformation of the heterocyclic six membered ring. The cyclotetraphosphazene ring shows a flattened crown-saddle conformation, the phosphorous atoms arranged nearly at the corners of a square. Influenced by crystal packing there exist small deviations from the molecular mirror plane and also differences in conformation between the two molecules of the asymmetric unit.     

Neue 1λ5, 3λ5-[1,3]Diphosphinine mit Thio- und Selenophosphonsäureresten – Darstellung,Kristallstruktur, NMR-Daten und Komplexbildung mit PdII

Diphosphabenzenes. VI. New 1λ⁵, 3λ⁵-[1,3]Diphosphinines with Thio and Seleno Phosphonic Acid Groups – Preparation, Crystal Structure, NMR Data, and Coordination to Pd^II Preparation of N,N,N′,N′-tetraethyl-P-phenylethinyl phosphonothioacid diamide ( 2 ) and the corresponding phosphonoselenoacid diamide ( 3 ) are described. 2 and 3 react with 1,1,3,3-tetrakis(dimethylamino)-1λ⁵,3λ⁵-diphosphete ( 1 ) to yield 1λ⁵,3λ⁵-[1,3]diphosphinine derivatives 4 and 5 . With (bzl)₂Cl₂Pd 5 forms the coordination compound 6 . All new compounds 2–6 are characterized by their nmr and ir spectra, the structures of 4–6 are further elucidated by X-ray structural analyses.     

Palladium(II)‐Komplexe des 1,1,3,3,5,5‐Hexakis(dimethylamino)‐λ5‐[1,3,5]triphosphinins

Palladium(II) Complexes of 1,1,3,3,5,5‐Hexakis(dimethylamino)‐λ⁵‐[1,3,5]triphosphinine 1,1,3,3,5,5‐Hexakis(dimethylamino)‐1λ⁵‐3λ⁵‐5λ⁵‐[1,3,5]triphosphinine ( 5 ) reacts with (benzonitrile)₂PdCl₂ to give the chelate complex dichloro(dodeca‐N‐methyl‐1λ⁵,3λ⁵,5λ⁵‐1,3,5‐triphosphinine‐1,1,3,3,5,5‐hexaamin‐C²,C⁴)palladium ( 6 ). In a pyridine‐d₅ solution of 6 the complex dichloro(dodeca‐N‐methyl‐1λ⁵,3λ⁵,5λ⁵‐1,3,5‐triphosphinine‐1,1,3,3,5,5‐hexaamin‐C²)((²H₅)pyridine‐N)palladium ( 7 ) is formed. The solute 7 could not be isolated as a solid, because elimination of the solvent regenerates 6 quantitatively. Properties, nmr and ir spectra of 6 and 7 are reported. 6 is characterized by the results of an X‐ray structural analysis.     

Methoxy[meso‐5,10,15,20‐tetrakis(2,6‐difluorophenyl)porphyrinato]­iron(III), [Fe(TDFPP)(OCH3)]

The crystal structure of the title compound, [Fe(C₄₄H₂₀F₈N₄)(CH₃O)], has been determined. The Fe atom lies 0.485 (1) Å out of the plane of the four N atoms to which it is coordinated and from the inversion centre at the origin of the unit cell. The methoxy group is axially coordinated to the Fe atom with O—Fe—N angles of 106.3 (2) and 102.4 (2)°, a C—O—Fe angle of 128.3 (5)° and an Fe—O distance of 1.788 (5) Å. Di­fluoro­phenyl rings are tilted from the porphyrin (por) plane with torsion angles of ?68.1 (6) and 77.7 (5)° across the two C_por—­C—C—C_ar systems.     

A tungsten-183NMR study of cis and trans isomers of [W(CO)4(PPh3)(PR3)](PR3 = phosphine, phosphite)

Tungsten-183 NMR data are reported for the complexes cis- and trans-[W(CO)4(PPh3)(PR3)] (PR3 = PnBu3, PMe3, PMe2Ph, PMePh2, PPh3, P(4-C6H4OMe)3, P(4-C6H4Me)3, P(4-C6H4F)3, P(OMe)3, P(OEt)3, P(OPh)3 and for PCy3, P(NMe2)3(trans isomer only). The 183W chemical shift (obtained by indirect detection using 31P) is found to be related to the PR3 ligand parameters nu and theta (Tolman electronic factor and cone angle, respectively) for the cis isomers and to nu (but only poorly to theta) for the trans isomers. The 183W-31P spin coupling constant is also related, less clearly for P-C than for P-N and P-O bonded ligands, to nu. Chemical shifts are referenced to an absolute frequency Xi (183W) = 4.15 MHz, which is proposed as a calibration standard for 183W NMR. The structures of cis-[W(CO)4(PPh3)(PMe3)] and cis-[W(CO)4(PPh3){P(4-C6H4F)3}] are reported.     

Isomerism and fluxional behaviour in η2 -vinyl complexes resulting in inversion of configuration at an asymmetric carbon atom. The crystal and molecular structures of two isomeric forms of [MoCl{η2 -C(CF3)C(CF3)(PEt3)} (CF3CCCF3)(η5 -C5H5)]

η² -Vinyl complexes [MCl{η² -C(CF₃)C(CF₃)L} (CF₃CCCF₃)(η⁵ -C₅H₅)] (M = Mo, W: L = tertiary phosphine or phosphite or pyridine) have been shown by NMR and X-ray diffraction studies to exist in two distinct isomeric forms which exhibit (a) different orientations of the η² -vinyl ligand (b) different configurations at the asymmetric carbon atom of the η² -vinyl ligand: variable temperature NMR studies reveal fluxional behaviour thought to involve reversible inversion of configuration at this carbon atom.     

Chiral and Nonchiral [OsX2(diphosphane)(diamine)] (X: Cl,OCH2CF3) Complexes for Fast Hydrogenation of Carbonyl Compounds

The osmium complexes trans‐[OsCl₂(dppf)(diamine)] (dppf: 1,1′‐bis(diphenylphosphino)ferrocene; diamine: ethylenediamine in 3 , propylenediamine in 4 ) were prepared by the reaction of [OsCl₂(PPh₃)₃] ( 1 ) with the ferrocenyl diphosphane, dppf and the corresponding diamine in dichloromethane. The reaction of derivative 3 with NaOCH₂CF₃ in toluene afforded the alkoxide cis‐[Os(OCH₂CF₃)₂(dppf)(ethylenediamine)] ( 5 ). The novel precursor [Os₂Cl₄(P(m‐tolyl)₃)₅] ( 2 ) allows the synthesis of the chiral complexes trans‐[OsCl₂(diphosphane)(1,2‐diamine)] ( 6 – 9 ; diphosphane: (R)‐[6,6′‐dimethoxy(1,1′‐biphenyl)‐2,2′‐diyl]bis[1,1‐bis(3,5‐dimethylphenyl)phosphane] (xylMeObiphep) or (R)‐(1,1′‐binaphthalene)‐2,2′‐diylbis[1,1‐bis(3,5‐dimethylphenyl)phosphane] (xylbinap); diamine=(R,R)‐1,2‐diphenylethylenediamine (dpen) or (R,R)‐1,2‐diaminocyclohexane (dach)), obtained by the treatment of 2 with the diphosphane and the 1,2‐diamine in toluene at reflux temperature. Compounds 3 – 5 in ethanol and in the presence of NaOEt catalyze the reduction of methyl aryl, dialkyl, and diaryl ketones and aldehydes with H₂ at low pressure (5 atm), with substrate/catalyst (S/C) ratios of 10 000–200 000 and achieving turnover frequencies (TOFs) of up to 3.0×10⁵ h^?1 at 70 °C. By employment of the chiral compounds 6 – 9 , different ketones, including alkyl aryl, bulky tert‐butyl, and cyclic ketones, have successfully been hydrogenated with enantioselectivities up to 99 % and with S/C ratios of 5000–100 000 and TOFs of up to 4.1×10⁴ h^?1 at 60 °C.