Chlorotris(N,N′‐dicyclohexylthiourea‐S)tellurium(II) chloride,a tellurium complex with a TeClS3 coordination sphere

During the synthesis of a series of square‐planar [TeCl₂(stu)₂] complexes, where stu represents bulky di‐ or tetrasubstituted thio­ureas, the title compound, [TeCl{(C₆H₁₁NH)₂CS}₃]Cl or C₃₉H₇₂ClN₆S₃Te⁺·Cl^?, was the unexpected result when stu was N,N′‐di­cyclo­hexyl­thio­urea. The complex is square planar, with Te—S distances of 2.5803 (4), 2.6211 (4) and 2.8214 (4) Å, and a Te—Cl distance of 2.6485 (4) Å, indicating a small trans influence of the thio­urea ligand.     

trans‐Tetrachlorobis(N,N′‐dimethyl­imidazolidine‐2‐thione)tellurium(IV), a thiourea complex of tellurium with asymmetric Te—S bonds

The structure of the title compound, [TeCl₄(C₅H₁₀N₂S)₂] or C₁₀H₂₀Cl₄N₄S₂Te, has been solved in order to study the stereochemical activity of the lone pair of electrons on Te^IV. The two crystallographically independent mol­ecules in the asymmetric unit both show a distorted octahedral coordination of the Te atom. The two Te—S bonds are trans to each other in both mol­ecules and are greatly asymmetric, with bond lengths of 2.5686 (7) versus 2.8557 (8) Å and 2.5859 (7) versus 2.8165 (9) Å. The Te—Cl bond lengths lie in the range 2.5236 (7)–2.5589 (8) Å. The asymmetric Te—S bonds and a large S—Te—Cl angle of ca 97° involving the long Te—S bonds indicate stereochemical activity of the lone pair of electrons on Te.     

Thiosemicarbazonates of Ruthenium(II): Crystal Structures of [Bis(triphenylphosphine)][bis(N‐phenyl‐pyridine‐2‐carbaldehyde Thiosemicarbazonato)]ruthenium(II) and [Bis(diphenylphosphino)butane][bis(salicylaldehyde Thiosemicarbazonato)]ruthenium(II)

Reaction of RuCl₂(PPh₃)₃ with N‐Phenyl‐pyridine‐2‐carbaldehyde thiosemicarbazone (C₅H₄N–C²(H)=N³‐N²H–C¹(=S)N¹HC₆H₅, Hpytsc‐NPh) in presence of Et₃N base led to loss of ‐N²H‐proton and yielded the complex [Ru(pytsc‐NPh)₂(Ph₃P)₂] ( 1 ). Similar reactions of precursor RuCl₂[(p‐tolyl)₃P]₃ with a series of thiosemicarbazone ligands, viz. pyridine‐2‐carbaldehyde thiosemicarbazone (Hpytsc), salicylaldehyde thiosemicarbazone (H₂stsc), and benzaldehyde thiosemicarbazone (Hbtsc), have yielded the complexes, [Ru(pytsc)₂{(p‐tolyl)₃P}₂] ( 2 ), [Ru(Hstsc)₂{(p‐tolyl)₃P}]₂ ( 3 ), and [Ru(btsc)₂{(p‐tolyl)₃P}₂] ( 4 ), respectively. The reactions of precursor Ru₂Cl₄(dppb)₃ {dppb = Ph₂P–(CH₂)₄–PPh₂} with H₂stsc, Hbtsc, furan‐2‐carbaldehyde thiosemicarbazone (Hftsc) and thiophene‐2‐carbaldehyde thiosemicarbazone (Httsc) have formed complexes of the composition, [Ru(Hstsc)₂(dppb)] ( 5 ), [Ru(btsc)₂(dppb)] ( 6 ), [Ru(ftsc)₂(dppb)] ( 7 ), and [Ru(ttsc)₂(dppb)] ( 8 ). The complexes have been characterized by analytical data, IR, NMR (¹H, ³¹P) spectroscopy and X‐ray crystallography ( 1 and 5 ). The proton NMR confirmed loss of –N²H– proton in all the compounds, and ³¹P NMR spectra reveal the presence of equivalent phosphorus atoms in the complexes. In all the compounds, thiosemicarbazone ligands coordinate to the Ru^II atom via hydrazinic nitrogen (N²) and sulfur atoms. The arrangement around each metal atom is distorted octahedral with cis:cis:trans P, P:N, N:S, S dispositions of donor atoms.     

Enantioselectivity and cis/trans-Selectivity in Dirhodium(II)-Catalyzed addition of diazoacetates to olefins

The Rh¹¹-catalyzed carbenoid addition of diazoacetates to olefins was investigated with [Rh₂{(4S)-phox}₄] ( 1 ;phox = tetrakis[(4S)-tetrahydro-4-phenyloxazol-2-one]), [Rh₂{(2S)-mepy}₄] ( 2 ; mepy = tetrakis[methyl (2S)-tetrahydro-5-oxopyrrole-2-carboxylate]), and [Rh₂(OAc)₄] ( 3 ). While catalysis with 2 and 3 afford preferentially trans-cyclopropanecarboxylates, the cis-isomers are the major products with 1 . In general, the enantioselectivities achieved with 1 and 2 are comparable. Additions catalyzed by 1 are strongly sensitive to steric effects. Highly substituted olefins afford cyclopropanes in only poor yield. The preferential cis-selectivity observed in reactions catalyzed by 1 is attributed to dominant interactions between the ligand of the catalyst and the substituents of both olefin and diazoacetate, which overrule the steric interactions between olefin and diazoacetate in the transition state for carbene transfer.     

Trans Influence of Triphenylstibine: Crystal Structures of cis‐[PtBr2(SbPh3)2], trans‐[PtBr(Ph)(SbPh3)2], [NMe4][PtBr3(SbPh3)], and cis‐[PtBr2(SbPh3)(PPh3)]

The work reports the unexpected reaction of diphenyldibromo antimonates (III) with PtCl₂ and cis‐[PtCl₂(PPh₃)₂]. The reaction gives triphenylstibine containing Pt^II complexes viz. cis‐[PtBr₂(SbPh₃)₂] ( 1 ), trans‐[[PtBr(Ph)(SbPh₃)₂] ( 2 ), [NMe₄][PtBr₃(SbPh₃)] ( 3 ), and cis‐[PtBr₂(PPh₃)(SbPh₃)] ( 4 ). All the complexes were characterised by elemental analyses, IR, Raman, ¹⁹⁵Pt NMR, FAB mass spectroscopy and X‐ray crystallography. A plausible mechanism via the phenyl migration is proposed for the formation of these complexes. The average Pt–Br distance in 1 is 2.456(2) Å, in 2 2.496 Å(trans to Ph) while in 3 it is 2.476 Å (trans to Sb) implying a comparable trans influence of Ph₃Sb and Ph₃P.     

Dinuclear Complexes of Copper(I) with Crown Ether‐containing N‐Thiophosphorylated Bis‐thioureas and 2,2′‐Bipyridine or 1,10‐Phenanthroline: Synthesis,Characterization, and Picrate Extraction Properties

Reaction of O,O′‐diisopropylthiophosphoric acid isothiocyanate (iPrO)₂P(S)NCS with 1,10‐diaza‐18‐crown‐6, 1,7‐diaza‐18‐crown‐6, or 1,7‐diaza‐15‐crown‐5 leads to the N‐thiophosphorylated bis‐thioureas N,N′‐bis[C(S)NHP(S)(OiPr)₂]‐1,10‐diaza‐18‐crown‐6 ( H₂L^I ), N,N′‐bis[C(S)NHP(S)(OiPr)₂]‐1,7‐diaza‐18‐crown‐6 ( H₂L^II ) and N,N′‐bis[C(S)NHP(S)(OiPr)₂]‐1,7‐diaza‐15‐crown‐5 ( H₂L^III ). Reaction of the potassium salts of H₂L^I–III with a mixture of CuI and 2,2′‐bipyridine ( bpy ) or 1,10‐phenanthroline ( phen ) in aqueous EtOH/CH₂Cl₂ leads to the dinuclear complexes [Cu₂(bpy)₂L^I–III] and [Cu₂(phen)₂L^I–III] . The structures of these compounds were investigated by ¹H, ³¹P{¹H} NMR spectroscopy, and elemental analysis. The crystal structures of H₂L^I and [Cu₂(phen)₂L^I] were determined by single‐crystal X‐ray diffraction. Extraction capacities of the obtained compounds in comparison to the related compounds 1,10‐diaza‐18‐crown‐6, N,N′‐bis[C(=CMe₂)CH₂P(O)(OiPr)₂]‐1,10‐diaza‐18‐crown‐6, N,N′‐bis[C(S)NHP(O)(OiPr)₂]‐1,10‐diaza‐18‐crown‐6 towards the picrate salts LiPic, NaPic, KPic. and NH₄Pic were also studied.     

Tetrakis[(4S)-4-phenyloxazolidin-2-one]dirhodium(II) and Its Catalytic Applications for Metal Carbene Transformations

The synthesis and X-ray structure of the binuclear complex tetrakis[(4S)-4-phenyloxazolidin-2-one]-dirhodium(II) ([Rh₂{(4S)-phox}₄]) are reported. Structure-selectivity comparisons are made for typical metal carbene transformations, such as inter- and intramolecular cyclopropane formation, intermolecular cyclopropene formation and intramolecular C–H insertions of diazoacetates and diazoacetamides. The enantioselectivity achieved in the [Rh₂{(4S)-phox}₄]-catalyzed reactions is intermediate between that of [Rh₂{(5S)-mepy}₄] and [Rh₂{(4R)-bnox}₄], which were described previously (mepy = methyl 5-oxopyrrolidine-2-carboxylate; bnox = 4-benzyloxazolidin-2-one). In contrast to other catalyzed intermolecular cyclopropane formations, those using [Rh₂{(4S)-phox}₄] result preferentially in formation of the cis-cyclopropane.     

Mononukleare und mehrfach verbrückte dinukleare Phthalocyaninate(1–/2–) des Yttriums durch Solvenz‐kontrollierte Kondensation; kleine Solvenz‐Cluster als Liganden

Mononuclear and Multiply Bridged Dinuclear Phthalocyaninates(1–/2–) of Yttrium by Solvent Controlled Condensation; Small Solvent Clusters as Ligands Green chlorophthalocyaninato(2–)yttrium(III), [Y(Cl)pc^2–] forms when yttrium chloride is heated with o‐phthalonitrile in 1‐chloronaphthalene. Black cis‐di(chloro)phthalocyaninato(1‐)yttrium(III), ^cis[Y(Cl)₂pc^–] is obtained as a stable intermediate by partial reduction. Both complexes are soluble in many O‐donor solvents and pyridine. The solubility in water is remarkable: [Y(Cl)pc^2–] dissolves with green, ^cis[Y(Cl)₂pc^–] with red‐violet color. Typical absorptions of the pc^2– ligand are observed at 14800 and 29700 cm^–1. A solvent dependent monomer‐dimer equilibrium is found for the pc^– radical. The monomer with absorptions at 12100 and 19900 cm^–1 is favored in non‐polar solvents, while in polar solvents the dimer with absorptions at 8700, 13200 and 18600 cm^–1 is preferred. cis‐Tri(dimethylformamide)chlorophthalocyaninato(2–)yttrium(III) etherate ( 1 ) crystallises from a solution of [Y(Cl)pc^2–] in MeOH/dmf, cis‐tetra(dimethylsulfoxide)phthalocyaninato(2–)yttrium(III) chloride etherate methanol disolvate ( 2 ) from thf/dmso, μ‐di(chloro)‐μ‐di〈di(pyridine)(μ‐water)〉di(phthalocyaninato(2–)‐ yttrium(III)) ( 5 ) from py, and cis‐(chloro)pyridine(triphenylphosphine oxide)phthalocyaninato(2–)yttrium(III) semi‐etherate ( 3 ) is obtained from a solution of [Y(Cl)pc^2–] and triphenylphosphine oxide in py. 1 condenses in MeOH yielding a (1 : 1)‐mixture ( 4 ) of μ‐di(chloro)di(〈trans‐(diwaterdimethanol)〉〈dimethanol〉phthalocyaninato(2–)yttrium(III)) ( 4 a ) and μ‐di(chloro)di(dimethylformamide〈dimethanol〉phthalocyaninato(2–)yttrium(III)) ( 4 b ); co‐ordinatively bound solvent clusters are in brakets. The structures of 1 – 5 have been established by X‐ray crystallography. Apart from 3 with hepta‐co‐ordinated yttrium, the metal ion prefers octa‐co‐ordination, and the bond arrangement around Y³⁺ is always a distorted quadratic antiprism. In the dinuclear complexes obtained by solvent controlled condensation both antiprisms share an edge by two μ‐Cl atoms in 4 , while in 5 the antiprisms are face‐shared by two trans positioned μ‐Cl atoms and μ‐O atoms, respectively. In 5 , the bent ^b〈{py}₂(μ‐H₂O)〉 cluster is stabilised by a combined interplanar bonding of pyridine by short N…H–O bonds (d(N…O) = 2.664(7) Å; 2.81(2) Å) and strong van‐der‐Waals interactions with the ecliptic pc^2– ligands. 4 a and 4 b contain the dimeric methanol cluster 〈(MeOH)₂〉, and 4 a in addition the cyclic heterotetrameric trans‐diwaterdimethanol cluster, trans^c〈(H₂O)₂(MeOH)₂〉. The neutral clusters co‐ordinatively bound to the Y atom are compared with structurally established cluster‐anions of type 〈(OMe)(MeOH)〉^–, linear ^l〈(OMe)(MeOH)₂〉^–, cyclic ^c〈(OH)₃(H₂O)₃〉^3–, ^b〈{H₂O}₂(μ‐O)〉^2–, and ^b{H₂O}₂(μ‐F)〉^–.     

The trans influence in mer‐tri­chloro­nitridobis­(tri­phenyl­arsine)­ruthenium(VI)

The title compound, mer‐[RuCl₃N(C₁₈H₁₅As)₂], is the first structurally characterized example of a nitride complex in which ruthenium is six‐coordinated to monodentate ligands only. The Ru[triple‐bond]N bond length [1.6161 (15) Å] is relatively long, and the trans influence of the nitride ligand is reflected by the difference between the Ru—Cl_trans and Ru—Cl_cis bond lengths [0.1234 (4) Å]. The N—Ru—Cl_trans axis is sited on a twofold axis.     

Coinage Metal Complexes of a Tellurium Diimide: cis→trans Isomerization and Metal–Metal Interactions

The different coordination behavior of the ligand tBuN=Te(μ-NtBu)₂Te=NtBu (L) towards Cu⁺ and Ag⁺ results from a cis→trans isomerization. The two Cu⁺ ions in [Cu₂L₃]²⁺ (shown schematically) bridge trans and cis isomers of the ligand, whereas the Ag⁺ ions in [Ag₂L₂]²⁺ link two trans ligands and exhibit a weak Ag⋅⋅⋅Ag interaction.     

Influence of Central Metalloligand Geometry on Electronic Communication between Metals: Syntheses,Crystal Structures,MMCT Properties of Isomeric Cyanido‐Bridged Fe2Ru Complexes,and TDDFT Calculations

To investigate how the central metalloligand geometry influences distant or vicinal metal‐to‐metal charge‐transfer (MMCT) properties of polynuclear complexes, cis‐ and trans‐isomeric heterotrimetallic complexes, and their one‐ and two‐electron oxidation products, cis/trans‐ [Cp(dppe)Fe^IINCRu^II(phen)₂CN‐Fe^II(dppe)Cp][PF₆]₂ (cis/trans‐ 1 [PF₆]₂), cis/trans‐[Cp(dppe)Fe^IINCRu^II(phen)₂CNFe^III‐(dppe)Cp][PF₆]₃ (cis/trans‐ 1 [PF₆]₃) and cis/trans‐[Cp(dppe)Fe^IIINCRu^II(phen)₂CN‐Fe^III(dppe)Cp][PF₆]₄ (cis/trans‐ 1 [PF₆]₄) have been synthesized and characterized. Electrochemical measurements show the presence of electronic interactions between the two external Fe^II atoms of the cis‐ and trans‐isomeric complexes cis/trans‐ 1 [PF₆]₂. The electronic properties of all these complexes were studied and compared by spectroscopic techniques and TDDFT//DFT calculations. As expected, both mixed valence complexes cis/trans‐ 1 [PF₆]₃ exhibited different strong absorption signals in the NIR region, which should mainly be attributed to a transition from an MO that is delocalized over the Ru^II‐CN‐Fe^II subunit to a Fe^III d orbital with some contributions from the co‐ligands. Moreover, the NIR transition energy in trans‐ 1 [PF₆]₃ is lower than that in cis‐ 1 [PF₆]₃, which is related to the symmetry of their molecular orbitals on the basis of the molecular orbital analysis. Also, the electronic spectra of the two‐electron oxidized complexes show that trans‐ 1 [PF₆]₄ possesses lower vicinal Ru^II→Fe^III MMCT transition energy than cis‐ 1 [PF₆]₄. Moreover, the assignment of MMCT transition of the oxidized products and the differences of the electronic properties between the cis and trans complexes can be well rationalized using TDDFT//DFT calculations.     

cis,cis,cis‐(Acetato‐O,O′)­bis­[1,2‐bis­(di­phenyl­phosphino)­ethane‐P,P′]­ruthenium(II) hexa­fluoro­phosphate di­methanol solvate

In the cation of the title complex, cis,cis,cis‐[Ru(η²‐O₂CMe)(dppe)₂]PF₆·2MeOH [dppe is 1,2‐bis­(di­phenyl­phosphino)­ethane, C₂₆H₂₄P₂], the Ru atom is in a pseudo‐octahedral coordination environment with two chelating dppe ligands and one chelating acetate ligand. Intra‐phosphine and intra‐acetate bond lengths and angles are unexceptional. Deviations from idealized octahedral coordination angles at ruthenium [O—Ru—O 59.43 (8)° and P—Ru—P 103.19 (2)°] presumably derive from constraints imposed by the chelate rings. The Ru—P distances for the mutually trans P‐donor atoms [2.3785 (6) Å] are significantly longer than those for the Ru—P linkages trans to the acetate ligand [2.3074 (6) Å]. The Ru1, C1 and C2 atoms lie on a twofold axis, and atom P3 of the anion lies on an inversion centre.     

The Cocrystallization of the Cubic [Ta6Br12(H2O)6][CuBr2X2]·10H2O and Triclinic [Ta6Br12(H2O)6]X2·trans‐[Ta6Br12(OH)4(H2O)2]·18H2O (X = Cl,Br, NO3) Phases with the Coexistence of [Ta6Br12]2+ and [Ta6Br12]4+ in the Latter

Cubic [Ta₆Br₁₂(H₂O)₆][CuBr₂X₂]·10H₂O and triclinic [Ta₆Br₁₂(H₂O)₆]X₂·trans‐[Ta₆Br₁₂(OH)₄(H₂O)₂]·18H₂O (X = Cl, Br, NO₃) cocrystallize in aqueous solutions of [Ta₆Br₁₂]²⁺ in the presence of Cu²⁺ ions. The crystal structures of [Ta₆Br₁₂(H₂O)₆]Cl₂·trans‐[Ta₆Br₁₂(OH)₄(H₂O)₂]·18H₂O ( 1 ) and [Ta₆Br₁₂(H₂O)₆]Br₂·trans‐[Ta₆Br₁₂(OH)₄(H₂O)₂]·18H₂O ( 3 )have been solved in the triclinic space group P&1macr; (No. 2). Crystal data: 1 , a = 9.3264(2) Å, b = 9.8272(2) Å, c = 19.0158(4) Å, α = 80.931(1)?, β = 81.772(2)?, γ = 80.691(1)?; 3 , a = 9.3399(2) Å, b = 9.8796(2) Å, c = 19.0494(4) Å; α = 81.037(1)?, β = 81.808(1)?, γ = 80.736(1)?. 1 and 3 consist of two octahedral differently charged cluster entities, [Ta₆Br₁₂]²⁺ in the [Ta₆Br₁₂(H₂O)₆]²⁺ cation and [Ta₆Br₁₂]⁴⁺ in trans‐[Ta₆Br₁₂(OH)₄(H₂O)₂]. Average bond distances in the [Ta₆Br₁₂(H₂O)₆]²⁺ cations: 1 , Ta‐Ta, 2.9243 Å; Ta‐Brⁱ , 2.607 Å; Ta‐O, 2.23 Å; 3 , Ta‐Ta, 2.9162 Å; Ta‐Brⁱ , 2.603 Å; Ta‐O, 2.24 Å. Average bond distances in trans‐[Ta₆‐Br₁₂(OH)₄(H₂O)₂]: 1 , Ta‐Ta, 3.0133 Å; Ta‐Brⁱ, 2.586 Å; Ta‐O(OH), 2.14 Å; Ta‐O(H₂O), 2.258(9) Å; 3 , Ta‐Ta, 3.0113 Å; Ta‐Brⁱ, 2.580 Å; Ta‐O(OH), 2.11 Å; Ta‐O(H₂O), 2.23(1) Å. The crystal packing results in short O···O contacts along the c axes. Under the same experimental conditions, [Ta₆Cl₁₂]²⁺ oxidized to [Ta₆Cl₁₂]⁴⁺ , whereas [Nb₆X₁₂]²⁺ clusters were not affected by the Cu²⁺ ion.     

Acetonyl­di­chloro­[(Z)‐2‐chloro‐2‐phenyl­vinyl]­tellurium(IV), helical chains of metal complexes

The primary geometry about the Te^IV atom in the title compound, [TeCl₂(C₈H₆Cl)(C₃H₅O)] or C₁₁H₁₁Cl₃OTe, is a pseudo‐trigonal‐bipyramidal arrangement, with two Cl atoms in apical positions, and the lone pair of electrons and C atoms in the equatorial plane. The Te^IV atom is involved in three secondary interactions, two intramolecular [Te?O = 2.842 (3) Å and Te?Cl3 = 3.209 (1) Å] and one intermolecular [Te?Cl = 3.637 (1) Å], the latter giving rise to a helical chain. These helices are linked by C—H?O interchain interactions.     

Cis-Trans Isomerism in Square Planar [TeX 2 (stu) 2 ] Complexes (X = Br − , I − ) with Bulky Substituted Thiourea (stu) Ligands. Syntheses and Structures of Four New Tellurium(II) Complexes

The complexes were synthesised by adding a hot solution of the appropriate substituted thiourea in MeOH (Br m complexes) or DMF (I m complexes) to a solution of TeO 2 dissolved in hot conc. HCl. The structures of the resulting four-coordinate square planar complexes, cis -[TeBr 2 {( i PrNH) 2 CS} 2 ] ( 1 ), cis -[TeBr 2 {( i BuNH) 2 CS} 2 ] ( 2 ), trans -[TeI 2 {( i PrNH) 2 CS} 2 ] ( 3 ), and trans -[TeI 2 {( i BuNH) 2 CS} 2 ] ( 4 ), were studied by means of X-ray crystallographic methods. The average Te-S bond length in 1 and 2 is 2.5364 Å. The corresponding average Te-Br bond length is 2.9639 Å, reflecting the stronger trans influences of the two thioureas as compared to that of bromide. In 3 and 4 where there is no trans influence affecting the Te-ligand bonds, the average Te-S and Te-I bond lengths are 2.6926 and 2.9761 Å respectively. Tetraalkyl- or arylsubstituted thioureas alone as well as bulky disubstituted thioureas together with I m ligands seem to favor formation of trans complexes.     

Ni(bipy)2Ni(CN)4, a new type of one‐dimensional square tetra­cyano complex

The one‐dimensional structure of catena‐poly­[[bis(2,2′‐bi­pyri­dyl‐1κ²N,N′)‐μ‐cyano‐1:2κ²N:C‐di­cyano‐2κ²C‐di­nickel(II)]‐μ‐cyano‐C:N], [Ni₂(CN)₄(C₁₀H₈N₂)₂]_n, consists of infinite zigzag chains running parallel to the c axis. The chains are composed of paramagnetic [Ni(bipy)₂]²⁺ cations (bricks; nickel on a twofold axis) linked by diamagnetic [Ni(CN)₄]^2? anions (mortar; nickel on an inversion center) via bridging cyano groups. The bridging cyano groups occupy cis positions in the cation and trans positions in the anion, giving rise to a new previously unknown CT‐type chain (i.e. cis–trans‐type) among square tetra­cyano complexes. The coordination polyhedron of the paramagnetic Ni atom (twofold symmetry) is a slightly deformed octahedron with the two Ni—N(bipy) bonds in cis positions being somewhat longer [2.112 (3) Å] than the remaining four Ni—N bonds with a mean value of 2.065 (6) Å. The bond distances and angles in the anion have typical values.     

Ein Beitrag zu Rhenium(II)‐, Osmium(II)‐ und Technetium(II)‐Thionitrosylkomplexen vom Typ [M(NS)Cl4py]—: Darstellung,Strukturen und EPR‐Spektren

A Contribution to Rhenium(II)‐, Osmium(II)‐, and Technetium(II)‐Thionitrosyl‐Complexes: Preparation, Structures, and EPR‐Spectra The reaction of [Re^VINCl₄]^— and [Os^VINCl₄]^— with S₂Cl₂ leads to the formation of the thionitrosyl complexes [M^II(NS)Cl₄]^— (M = Re, Os) which could not be isolated as pure compounds. Addition of pyridine to the reaction mixture results in the formation of the stable compounds trans‐(Ph₄P)[Os^II(NS)Cl₄py], trans‐(Hpy)[Os^II(NS)Cl₄py], trans‐(Ph₄P)[Re^II(NS)Cl₄py], and cis‐(Ph₄P)[Re^II(NS)Cl₄py]. The crystal structure analyses show for trans‐(Ph₄P)[Os^II(NS)Cl₄py] (monoclinic, P2₁/n, a = 12.430(3)Å, b = 18.320(4)Å, c = 15.000(3)Å, β = 114.20(3)°, Z = 4), trans‐(Hpy)[Os^II(NS)Cl₄py] (monoclinic, P2₁/n, a = 7.689(1)Å, b = 10.202(2)Å, c = 20.485(5)Å, β = 92.878(4)°, Z = 4), trans‐(Ph₄P)[Re^II(NS)Cl₄py] (triclinic, P1¯, a = 9.331(5)Å, b = 12.068(5)Å, c = 15.411(5)Å, α = 105.25(1)°, β = 90.23(1)°, γ = 91.62(1)°, Z = 2), and cis‐(Ph₄P)[Re^II(NS)Cl₄py] (monoclinic, P2₁/c, a = 10.361(1)Å, b = 16.091(2)Å, c = 17.835(2)Å, β = 90.524(2)°, Z = 4) M‐N‐S angles in the range 168‐175°. This indicates a nearly linear coordination of the NS ligand. The metal atom is octahedrally coordinated in all cases. The rhenium(II) thionitrosyl complexes (5d⁵ “low‐spin” configuration, S = 1/2) are studied by EPR in the temperature range 295 > T > 130 K. In addition to the detection of the complexes formed during the reaction of [Re^VINCl₄]^— with S₂Cl₂ EPR investigations on diamagnetically diluted powders and single crystals of the system (Ph₄P)[Re^II/Os^II(NS)Cl₄py] are reported. The ^{185, 187}Re hyperfine parameters are used to get information about the spin‐density distribution of the unpaired electron in the complexes under study. [Tc^VINCl₄]^— reacts with S₂Cl₂ under formation of [Tc^II(NS)Cl₄]^— which is not stable and decomposes under S₈ elimination and rebuilding of [Tc^VINCl₄]^— as found by EPR monitoring of the reaction.     

The Structure of cis‐[Chloro(dimethylsulfoxide)bis(1, 10‐phenanthroline)ruthenium(II)]‐tetraphenylborate, [RuCl(DMSO)(1, 10‐phen)2][BPh4]

The complex cis‐[RuCl(DMSO)(phen)₂]BPh₄, where DMSO is dimethylsulfoxide and phen is 1, 10‐phenanthroline, crystallizes in the monoclinic space group P2₁/c with a = 19.505(4), b = 10.045(2), c = 21.199(4) Å, β = 90.137(4)°, V = 4153(2) ų, Z = 4, D_calc = 1.430 g cm^—3. The ruthenium coordination geometry is that of a slightly distorted octahedron with a cis‐RuN₄ClS arrangement of the ligand donor atoms. The Ru—Cl distance is 2.421(1) Å and the Ru—S distance 2.250(2) Å. The four Ru—N distances are 2.057(6), 2.066(4), 2.073(4), and 2.086(4) Å with the Ru—N bond trans to Cl the second shortest and the Ru—N bond trans to S the longest one.     

Crystal and Molecular Structure of trans‐[IrCl(N2)(PiPr3)2]

Single crystals of trans‐[IrCl(N₂)(PⁱPr₃)₂] ( 1 ), obtained during studies on the reaction of [{Ir(μ‐Cl)(coe)₂}₂] (coe = cis‐cyclooctene) with tri‐iso‐propylphosphane in diethyl ether under dinitrogen atmosphere, have been analyzed by X‐ray crystallography (monoclinic, P2₁/c, Z = 2, a = 8.0855(9), b = 8.896(3), c = 16.539(3) Å; β = 93.124(11)°; V = 1187.9(4); T = 200(2) K). In the course of these studies under an atmosphere of dinitrogen or argon, the formation of a variety of phosphorus‐containing compounds was indicated using ³¹P{¹H} NMR spectroscopy.     

Experimental and quantum‐chemical studies of 1H, 13C and 15N NMR coordination shifts in Au(III), Pd(II) and Pt(II) chloride complexes with picolines

¹H, ¹³C and ¹⁵N NMR studies of gold(III), palladium(II) and platinum(II) chloride complexes with picolines, [Au(PIC)Cl₃], trans‐[Pd(PIC)₂Cl₂], trans/cis‐[Pt(PIC)₂Cl₂] and [Pt(PIC)₄]Cl₂, were performed. After complexation, the ¹H and ¹³C signals were shifted to higher frequency, whereas the ¹⁵N ones to lower (by ca 80–110 ppm), with respect to the free ligands. The ¹⁵N shielding phenomenon was enhanced in the series [Au(PIC)Cl₃] < trans‐[Pd(PIC)₂Cl₂] < cis‐[Pt(PIC)₂Cl₂] < trans‐[Pt(PIC)₂Cl₂]; it increased following the Pd(II) → Pt(II) replacement, but decreased upon the trans → cis‐transition. Experimental ¹H, ¹³C and ¹⁵N NMR chemical shifts were compared to those quantum‐chemically calculated by B3LYP/LanL2DZ + 6‐31G**//B3LYP/LanL2DZ + 6‐31G*. Copyright © 2008 John Wiley & Sons, Ltd.