Gemischtligandkomplexe des Technetiums. XV. Zur Reaktion von [TcNCl2(Me2PhP)3] mit Dialkyldithiocarbamaten und N,N-Dialkylthiocarbamoylbenzamidinen

Mixed-ligand Complexes of Technetium. XV. The Reaction of [TcNCl₂(Me₂PhP)₃] with Dialkyldithiocarbamates and N,N-Dialkylthio-carbamoylbenzamidines [TcN(Cl)(Me₂PhP)₂(Et₂dtc)], [TcN(Me₂PhP)(Et₂dtc)₂], and [TcN(Et₂dtc)₂] can be prepared by stepwise ligand exchange reactions starting from dichlorotris(dimethylphenylphosphine)nitridotechnetium(V), [TcNCl₂(Me₂PhP)₃], and diethyldithiocarbamate. In contrast to this, only one intermediate, [TcN(Cl)(Me₂PhP)₂(HEt₂tcb)], could be isolated during the reaction with N,N-Diethlthiocarbamoylbenzamidine, which yields the bis chelate [TcN(HEt₂tcb)₂]. [TcN(Me₂PhP)(Et₂dtc)₂] crystallizes in the monoclinic space group P2₁/c; a = 17.369(5) Å, b = 15.024(1) Å, c = 9.906(3) Å, β = 76.47(1)º, Z = 4. The phosphine is coordinated equatorially. The multiply bonded nitrogen ligand (Tc? N(1) 1.624(3) Å) strongly labilizes the trans positioned donor atom (distance Tc? S(4) 2.826(1) Å). [TcN(HEt₂tcb)₂] crystallizes in the triclinic space group P1 with a = 9.749(4) Å, b = 11.264(4) Å, c = 12.359(4) Å, α = 75.34(2)º, β = 79.69(2)º, γ = 87.55(2)º, Z = 2. The metal is five-coordinate with the nitrido donor atom occupying the apex of a square pyramid. It's basal plane is formed by the cis-coordinated chelate ligands. The technetium is situated over the basal plane by about 0.6 Å. The Tc?N distane was found to be 1.610(5) Å.     

[Tc(NBCl2Ph)Cl2(Me2PhP)3] und [Tc(NBH3)Cl2(Me2PhP)3] – die ersten Technetium‐Komplexe mit Nitridobrücken zwischen Technetium und Bor

[Tc(NBCl₂Ph)Cl₂(Me₂PhP)₃] and [Tc(NBH₃)Cl₂(Me₂PhP)₃] – the First Technetium Complexes with Nitrido Bridges between Technetium and Boron [TcNCl₂(Me₂PhP)₃] reacts with BCl₂Ph or BH₃ · THF at low temperatures under formation of complexes containing a nitrido bridge between technetium and boron. The compounds are instable and decompose at room temperature under cleavage of the N–B bonds. The pale‐purple [Tc(NBCl₂Ph)Cl₂(Me₂PhP)₃] crystallizes in the orthorhombic space group Fdd2. The Tc≡N bond is only slightly lengthened by the formation of the N–B bond of 1.564(4) Å. However, a considerable lengthening of the Tc–Cl bond in trans position to the nitrido ligand is observed which can be attributed to an decreasing of the structural trans influence of the nitrido moiety. A similar structural feature can be found in [Tc(NBH₃)Cl₂(Me₂PhP)₃] which is the first structurally characterized transition metal complex containing a nitrido bridge to unsubstituted borane.     

Rhenium(I) and Technetium(I) Tricarbonyl Complexes with Phosphoraneimines

[NEt₄]₂[Re(CO)₃Br₃] and [NEt₄]₂[Tc(CO)₃Cl₃] react with trimethylsilyltriphenylphosphoraneimine, Me₃SiNPPh₃, under exchange of the bromo ligands and the formation of cationic [M(CO)₃(HNPPh₃)₃]⁺ complexes (M = Re, Tc). The required protons are abstracted from the solvent CH₂Cl₂. The steric bulk of the organic ligands causes a marked distortion of the established coordination polyhedra from an idealized octahedron with bond angles between neighbouring donor atoms between 81.81(8)° and 96.66(8)°. The reaction of [NEt₄]₂[Re(CO)₃Br₃] with Me₃SiNP(Ph₂)CH₂PPh₂ in CH₂Cl₂ yields the neutral complex [Re(CO)₃Br{HNP(Ph₂)CH₂PPh₂)], which contains a neutral, chelate‐bonded (diphenylphosphinomethyl)diphenylphosphoraneimine ligand. A similar reaction with the bifunctional phosphoraneimine Me₃SiNP(Ph₂)CH₂(Ph₂)PNSiMe₃ gives only small amounts of a binuclear rhenium(I) complex of the composition [{Re(CO)₃Br₂}₂(HNP(Ph₂)CH₂(Ph₂)PNH)]^2‐, whereas the major amount of the bis‐phosphoraneimine undergoes an intramolecular rearrangement to yield [H₂NP(Ph₂)NP(Ph₂)CH₃]Br. An X‐ray structure analysis shows a widespread delocalization of electron density over the central part of the cation.     

Synthese,EPR und Röntgenkristallstrukturanalyse von mer-Trichloro(2,2′-bipyridin)nitridotechnetium(VI), einem neuen Nitridokomplex des Technetium(VI)

Synthesis, EPR and X-Ray Structure of mer-Trichloro(2,2′-bipyridine)nitridotechnetium(VI) — a new Technetium(VI) Nitrido Complex mer-Trichloro(2,2′-bipyridine)nitridotechnetium(VI) has been prepared by the reaction of (NBu₄)[TcNCl₄] with 2,2′-bipyridine in acetonitrile, whereas the same procedure gives in methanol the technetium(V) cation [TcNCl(bipy)₂]⁺. The EPR spectrum of [TcNCl₃(bipy)] suggests a meridional coordination of the three chloro ligands. [TcNCl₃(bipy)] crystallizes monoclinic in the space group P2₁/n; a = 8.572(1), b = 15.462(1), c = 10.110(1) Å, β = 104.21(1)°, Z = 4. The R value converged at 0.034 on the basis of 3 040 reflections. The technetium atom is distorted octahedrally coordinated with the chloro ligands meridionally cis with respect to the nitrido nitrogen. The Tc? N(1) bond length is 1.669(4) Å, and the Tc? N(3) bond (2.371(4) Å) is significantly lengthened due to the structural trans labilizing influence of the “N^3?” ligand.     

Gemischtligandkomplexe des Technetiums. XVI. Darstellung und Struktur von (1,2-Dicyanoethen-1,2-dithiolato)bis(dimethylphenylphosphan)nitridotechnetium (V), [TcN(Me2PhP)2(mnt)]

Mixed-Ligand Complexes of Technetiums. XVI Synthesis and Structure of (1,2-Dicyanoethene-1,2-dithiolato)bis(dimethylphenylphosphine)nitridotechnetium(V), [TcN(Me₂PhP)₂(mnt)] [TcN(Me₂PhP)₂(mnt)] is formed from [TcNCl₂(Me₂PhP)₃] and one equivalent of the sodium salt of 1,2-dicyanoethene-1,2-dithiolate (Na₂mnt). The same reaction yields [TcN(mnt)₂]^2?, when a large excess of the ligand and long reaction periods are applied. The complex anion can be isolated as tetraalkylammonium or tetraphenylarsonium salts. [TcN(Me₂PhP)₂(mnt)] crystallizes in the triclinic space group P1 (a = 10.000(5), b = 14.182(6), c = 17.77(1) Å, α = 98.77(3), β = 103.77(3), γ = 104.55(3)°; Z = 4). The coordination sphere is a square pyramid with the sulfur and phosphorus atoms as basal plane. Tc is situated out of this plane by 0.56 Å towards the nitrido ligand.     

[Au(Et2dtc)2][TcNCl4] – Darstellung und Struktur

[Au(Et₂dtc)₂][TcNCl₄] – Synthesis and Structure [Au(Et₂dtc)₂][TcNCl₄] (Et₂dtc^– = N,N‐diethyldithiocarbamate) is formed by the reaction of [Au(CO)Cl] with [TcN(Et₂dtc)₂] in dichloromethane. The solid state structure of the compound is characterized by a large triclinic unit cell (space group, P1, a = 9.422(2), b = 22.594(5), c = 32.153(7) Å, α = 72.64(1), β = 85.19(1), γ = 86.15(1)°, Z = 12) and shows an unusual arrangement due to long‐range contacts between the technetium atoms and sulfur atoms of the [Au(Et₂dtc)₂]⁺ units (3.45–3.56 Å) which assemble two anions and one cation to {[TcNCl₄][Au(Et₂dtc)₂] · [TcNCl₄]}^– moieties.     

Reactions of Nitridotechnetium(V) Complexes with Boranes

Nitrido bridges between technetium and boron were formed during reactions of [TcN(PMe₂Ph)(Et₂dtc)₂] (Et₂dtc^? = diethyldithiocarbamate) and BH₃ or BPhCl₂ at low temperatures. X‐Ray structure determinations show that the products contain almost linear Tc–N–B bonds with Tc–N distances which are only slightly lengthened with respect to the triple bonds in the precursor molecule. However, a significant lengthening of the Tc–S bond trans to the nitrido ligand is detected by the decrease of the structural trans influence of “N^3?”N. The compounds are instable and decompose at room temperature under cleavage of the N–B bonds. A reaction between [TcNCl₂(PPh₃)₂] and BCl₃ does not yield a product with a nitrido bridge. Prolonged heating in dichloromethane results in decomposition of the technetium complex and the formation of (HPPh₃)₂[TcCl₆]. Hydrogen bonds are established between the complex anion and each two counter ions.     

Synthesis and Structure of [NbCl3(NPPh2Fc)2]: The First Example of a Complex Containing a Redox‐functionalised Phosphaneiminato Ligand

Reaction of Me₃SiNPPh₂Fc (Fc = ferrocenyl) with niobium pentachloride affords [NbCl₃(NPPh₂Fc)₂], whose redox‐functionalised phosphaneiminato ligands exhibit remarkably different bend angles at nitrogen according to a crystal structure analysis.     

Sulfur‐linked Phenolates as Ligands for the Syntheses of Low‐Nuclearity Iron(III) Complexes

Exploiting thiacalix 4 arene and sulfur‐bridged bisphenolates as ligands for bioinorganic studies involving iron(III) requires the prior development of synthetic routes (varying substituents and reaction conditions) to construct complexes with low nuclearities and accessible coordination sites, which was in the focus of this investigation. Treating p‐tert‐butylthiacalix 4 arene (H₄TC) and 1, 4‐dimethyl‐p‐tert‐butylthiacalix 4 arene (Me₂H₂TC) with Fe[N(SiMe₃)₂]₃ yielded in the formation of the iron(III) complexes [(Me₃SiTC)₂Fe₂] ( 1 ) and [(Me₂TC)₃Fe₂] ( 3 ), respectively. While 1 is a sandwich compound, in 3 one [Me₂TC]^2– unit is bridging two [Me₂TCFe]⁺ moieties. Employing thiobisphenolates as ligands it turned out, that in dependence on the residues R and the preparation method it is possible to selectively access sandwich, anionic or neutral complexes, which were shown to contain central high‐spin iron(III) atoms. The syntheses, structures, and electronic properties of three iron(III) bisphenolate complexes, [^ClL₂Fe]NEt₃H ( 4 ), [^MeLFeCl₂]NEt₃H ( 5 ), and [^tBuLFeCl(thf)] ( 7 ) are discussed.     

[W(NPPh3)4]Cl2 — Ein Phosphaniminato-Komplex mit einem Wolfram-Dikation

[W(NPPh₃)₄]Cl₂ — a Phosphoraneiminato Complex with a Dication of Tungsten The title compound has been prepared by the reaction of Me₃SiNPPh₃ with WNCl₃ and WO₂Cl₂, respectively, in acetonitrile, forming colourless crystals, which were characterized by IR spectroscopy and by an X-ray structure determination. Space group P2₁/n, Z = 4, 4 424 observed unique reflections, R = 0.045. Lattice dimensions at 20°C: a = 1 206.5(2), b = 2 225.3(2), c = 2 421.0(3) pm, β = 101.09(1)°. In the dication [W(NPPh₃)₄]²⁺ the tungsten atom is surrounded in a tetrahedral fashion by the four nitrogen atoms of the phosphoraneiminato ligands. The bond lengths WN and PN correspond with double bonds.     

Reaktionen silylierter Phosphanimine mit Iodmonochlorid und Iodtrichlorid. Die Kristallstrukturen von [Me3SiNPMe3 · ICl], [Ph3PNCl · ICl] und [Me3PN(H)PMe3] [ICl2]2

Reactions of Silylated Phosphorane Imines with Iodine Monochloride and Iodine Trichloride. The Crystal Structures of [Me₃SiNPMe₃ · ICl], [Ph₃PNCl · ICl], and [Me₃PN(H)PMe₃][ICl₂]₂ The donor-acceptor complex [Me₃SiNPMe₃ · ICl] has been prepared from Me₃SiNPMe₃ and ICl in acetonitrile solution forming yellow-orange crystals. [Ph₃PNCl · ICl] can be prepared by the reaction of Me₃SiNPPh₃ with ICl₃ in dichloromethane solution forming pale yellow crystals. [Me₃PN(H)PMe₃][ICl₂]₂ is formed in a small amount by a slow reaction of Me₃SiNPMe₃ with ICl₃ in CCl₄ suspension in the presence of traces of moisture. All samples are characterized by IR spectroscopy and by X-ray structure analyses. [Me₃SiNPMe₃ · ICl] (1) : Space group Iba2, Z = 8, structure solution with 1 727 observed unique reflections, R = 0.051. Lattice dimensions at ?60°C: a = 1 510.7, b = 1 862.8, c = 988.9 pm. 1 has a molecular structure in which the N atom of the phosphorane imine is connected with the iodine atom of the ICl molecule in a linear arrangement N? I? Cl. Bond lengths N? I = 222.7 pm, I? Cl = 265.1 pm. [Ph₃PNCl · ICl] (2) : Space group Pna2₁, Z = 4, structure solution with 1 530 observed unique reflections, R = 0.030. Lattice dimensions at 20°C: a = 1 522.8, b = 1 408.3, c = 865.8 pm. 2 has a molecular structure in which the N atom of the N chlorophosphorane imine is connected with the iodine atom of the ICl molecule in a linear arrangement. Bond lengths N? Cl = 174.4 pm, N? I = 229.5 pm, I? Cl = 251.2 pm. [Me₃PN(H)PMe₃][ICl₂]₂ (3) : Space group P2₁/c, Z = 4, structure solution with 1 989 observed unique reflections, R = 0.029. Lattice dimensions at ?50°C: a = 1 223.1, b = 1 090.2, c = 1 482.8 pm, β = 112.21°. 3 consists of [Me₃PN(H)PMe₃]²⁺ ions and ICl₂^? anions. The PNP bond angle of the dication amounts to 134.4° with PN distances of 165.6 and 166.1 pm, approximately according to double bonds.     

Coordination Adducts of Niobium(V) and Tantalum(V) Azide M(N3)5 (M=Nb,Ta) with Nitrogen Donor Ligands and their Self‐Ionization

Several new donor–acceptor adducts of niobium and tantalum pentaazide with N‐donor ligands have been prepared from the pentafluorides by fluoride–azide exchange with Me₃SiN₃ in the presence of the corresponding donor ligand. With 2,2′‐bipyridine and 1,10‐phenanthroline, the self‐ionization products [MF₄(2,2′‐bipy)₂]⁺[M(N₃)₆]⁻, [M(N₃)₄(2,2′‐bipy)₂]⁺[M(N₃)₆]⁻ and [M(N₃)₄(1,10‐phen)₂]⁺[M(N₃)₆]⁻ were obtained. With the donor ligands 3,3′‐bipyridine and 4,4′‐bipyridine the neutral pentaazide adducts (M(N₃)₅)₂⋅L (M=Nb, Ta; L=3,3′‐bipy, 4,4′‐bipy) were formed.     

Coordination Adducts of Niobium(V) and Tantalum(V) Azide M(N3)5 (M=Nb,Ta) with Nitrogen Donor Ligands and their Self‐Ionization

Several new donor–acceptor adducts of niobium and tantalum pentaazide with N‐donor ligands have been prepared from the pentafluorides by fluoride–azide exchange with Me₃SiN₃ in the presence of the corresponding donor ligand. With 2,2′‐bipyridine and 1,10‐phenanthroline, the self‐ionization products [MF₄(2,2′‐bipy)₂]⁺[M(N₃)₆]^?, [M(N₃)₄(2,2′‐bipy)₂]⁺[M(N₃)₆]^? and [M(N₃)₄(1,10‐phen)₂]⁺[M(N₃)₆]^? were obtained. With the donor ligands 3,3′‐bipyridine and 4,4′‐bipyridine the neutral pentaazide adducts (M(N₃)₅)₂?L (M=Nb, Ta; L=3,3′‐bipy, 4,4′‐bipy) were formed.     

Bis(phosphinimino)methanides as ligands in divalent lanthanide and alkaline earth chemistry - synthesis, structure, and catalysis

Divalent bis(phosphinimino)methanide lanthanide complexes of composition [{(Me₃SiNPPh₂)₂CH}EuI(THF)]₂ and [{(Me₃SiNPPh₂)₂CH}YbI(THF)₂] have been prepared by a salt metathesis reactions of K{CH(PPh₂NSiMe₃)₂} and LnI₂. Further reactions of these complexes with [K(THF)_nN(PPh₂)₂] led selectively to the heteroleptic amido complexes [{(Me₃SiNPPh₂)₂CH}Ln{(Ph₂P)₂N}(THF)] (Ln = Eu, Yb). The ytterbium complex can also be obtained by reduction of [{CH(PPh₂NSiMe₃)₂}Yb{(Ph₂P)₂N}Cl] with elemental potassium. The single crystals of [{(Me₃SiNPPh₂)₂CH}Ln{(Ph₂P)₂N}(THF)] contain enantiomerically pure complexes. As a result of the similar ionic radii of the divalent lanthanides and the heavier alkaline earth metals some similarities in coordination chemistry of the bis(phosphinimino)methanide ligand were anticipated. Therefore, MI₂ (M = Ca, Sr, Ba) was reacted with K{CH(PPh₂NSiMe₃)₂} to give [{(Me₃SiNPPh₂)₂CH}CaI(THF)₂], [{(Me₃SiNPPh₂)₂CH}SrI(THF)]₂, and [{(Me₃SiNPPh₂)₂CH}BaI(THF)₂]₂, respectively. As expected the Sr and Eu complexes and the Ca and Yb complexes are very similar, whereas for the Ba compound, as a result of the large ion radius, a different coordination sphere is observed. For all new complexes the solid-state structures were established by single crystal X-ray diffraction. In the solid-state the {CH(PPh₂NSiMe₃)₂}⁻ ligand acts as tridentate donor forming a long methanide carbon metal bond. Thus, all complexes presented can be considered as organometallic compounds. [{(Me₃SiNPPh₂)₂CH}YbI(THF)₂] was also used as precatalyst for the intramolecular hydroamination/cyclization reaction of different aminoalkynes and aminoolefines. Good yields but moderate activities were observed.     

Technetium Complexes with 2‐Mercapto‐methyltetrazolate

2‐Mercapto‐methyltetrazolate, Smetetraz^–, acts as monoanionic, monodentate ligand in a number of technetium compounds. Anionic Tc^V complexes of the types [TcO(Smetetraz)₄]^– and [TcN(Smetetraz)₄]^2– are formed when (Bu₄N)[Tc^VOCl₄] or (Bu₄N)[Tc^VINCl₄], respectively, react with Na(Smetetraz). Reduction of the metal takes place in the latter case. (Bu₄N)₂[TcN(Smetetraz)₄] crystallises in the monoclinic space group Pc (a = 9.701(5), b = 17.570(5), c = 16.821(10) Å, β = 96.50(3)°, Z = 2). The Tc atom is situated 0.580(3) Å above the basal plane of a square pyramid which is formed by the sulfur atoms and the nitrido ligand as its apex. The Tc–S bond lengths lie between 2.384(3) and 2.410(3) Å. [Tc(PPh₃)(Smetetraz)₃(CH₃CN)] is formed during the reaction of [TcCl₃(PPh₃)₂(CH₃CN)] with NaSmetetraz as blue needles with co‐crystallised solvent toluene (space group C2/c, a = 24.188(4), b = 14.373(1), c = 25.617(5) Å, β = 109.48(1)°, Z = 8). The metal atom is coordinated by PPh₃ and CH₃CN in the axial position of a trigonal bipyramid. All three aryl rings are on the sterically less strained side of the plane defined by the sulfur atoms. The Tc–S bond lengths range between 2.233(2) and 2.247(2) Å.     

Phosphaniminato-Trichloroselenate(II): Synthese und Kristallstrukturen von [SeCl(NPPh3)2]+SeCl3− und [Me3SiN(H)PMe3]2+[Se2Cl6]2−

Phosphorane Iminato-Trichloroselenates(II): Syntheses and Crystal Structures of [SeCl(NPPh₃)₂]⁺SeCl₃^? and [Me₃SiN(H)PMe₃]₂⁺[Se₂Cl₆]^2? [SeCl(NPPh₃)₂]⁺SeCl₃^? has been synthesized by the reaction of Se₂Cl₂ with Me₃SiNPPh₃ in acetonitrile solution, forming orangered crystals, whereas red crystals of [Me₃SiN(H)PMe₃]₂⁺[Se₂Cl₆]^2? were obtained by the reaction of Me₃SiNPMe₃ with SeOCl₂ in acetonitrile solution. Both complexes were characterized by X-ray structure determinations. [SeCl(NPPh₃)₂]⁺SeCl₃^?: Space group P2₁/n, Z = 4, structure solution with 7 489 observed unique reflections, R = 0.057. Lattice dimensions at ?60°C: a = 1 117.0; b = 2 241, c = 1 407.5 pm, β = 95.61°. In the cation [SeCl(NPPh₃)₂]⁺ the selenium atom is φ-tetrahedrally coordinated by the chlorine atom and by the nitrogen atoms of the phosphorane iminato ligands, whereas the anion SeCl₃^? has a T-shaped structure with φ-trigonal-bipyramidale surrounding of the selenium atom. [Me₃SiN(H)PMe₃]₂⁺[Se₂Cl₆]^2?: Space group P2₁/c, Z = 4, structure solution with 2 093 observed unique reflections, R = 0.080. Lattice dimensions at ?70°C: a = 956, b = 828, c = 1 973 pm, β = 93.80°. The structure consists of [Me₃SiN(H)PMe₃]⁺ ions and planar [Se₂Cl₆]^2? anions, in which the selenium atoms are bridged nearly symmetrically by two chlorine atoms.     

Neue nitridoverbrückte Dreikernkomplexe des Rheniums

New Trinuclear Rhenium Complexes with Bridging Nitrido Ligands Trinuclear complexes with bridging nitrido ligands between the rhenium atoms are formed when [ReN(Et₂dtc)₂ · (Me₂PhP)] (Et₂dtc^– = N,N‐diethyldithiocarbamate) reacts with TlCl or Pr(O₃SCF₃)₃. [Cl(Me₂PhP)₂(Et₂dtc)Re≡N–Re(N) · Cl₂(Me₂PhP)–N≡Re(Et₂dtc)(Me₂PhP)₂Cl] and [(Et₂dtc)₂ · (Me₂PhP)Re≡N–Re(N)(Et₂dtc)(Me₂PhP)–N≡Re(Me₂PhP) · (Et₂dtc)₂]⁺ contain two almost linear, asymmetric nitrido bridges. Additional, terminal nitrido ligands are located at the middle rhenium atoms.     

Oxorhenium(V) Complexes with 1,3,4‐Triphenyl‐1,2,4‐triazol‐5‐ylidene

Reactions of the oxorhenium(V) complexes [ReOX₃(PPh₃)₂] (X = Cl, Br) with the N‐heterocyclic carbene (NHC) 1,3,4‐triphenyl‐1,2,4‐triazol‐5‐ylidene (L^Ph) under mild conditions and in the presence of MeOH or water give [ReOX₂(Y)(PPh₃)(L^Ph)] complexes (X = Cl, Br; Y = OMe, OH). Attempted reactions of the carbene precursor 5‐methoxy‐1,3,4‐triphenyl‐4,5‐dihydro‐1H‐1,2,4‐triazole ( 1 ) with [ReOCl₃(PPh₃)₂] or [NBu₄][ReOCl₄] in boiling xylene resulted in protonation of the intermediately formed carbene and decomposition products such as [HL^Ph][ReOCl₄(OPPh₃)], [HL^Ph][ReOCl₄(OH₂)] or [HL^Ph][ReO₄] were isolated. The neutral [ReOX₂(Y)(PPh₃)(HL^Ph)] complexes are purple, airstable solids. The bulky NHC ligands coordinate monodentate and in cis‐position to PPh₃. The relatively long Re–C bond lengths of approximate 2.1Å indicate metal‐carbon single bonds.     

Synthese und Kristallstrukturen der heteronuklearen Nitrido‐Komplexe [(Me2PhP)3(MeCN)ClRe≡N–MCl5] mit M = Sn und Zr

Synthesis and Structures of the Dinuclear Nitrido Complexes [(Me₂PhP)₃(MeCN)ClRe≡N–MCl₅] with M = Sn and Zr The water sensitive complexes [(Me₂PhP)₃(MeCN)ClRe≡N–MCl₅] (M = Sn ( 1 ) und Zr ( 2 )) are obtained in dichloromethane from [ReNCl₂(PMe₂Ph)₃] and the acetonitrile adducts of SnCl₄ or ZrCl₄. The compounds crystallize as dichloromethane solvate isotypically with [(Me₂PhP)₃(MeCN)ClRe≡N–TiCl₅] · CH₂Cl₂ in the space group P2₁/n. From toluene crystallize monoclinic crystals of 1 · MeCN · C₇H₈. In the diamagnetic complexes 1 and 2 an anion [MCl₅]^– coordinates to the nitrido ligand of the cationic complex [ReNCl(MeCN)(PMe₂Ph)₃]⁺. The resulting nitrido bridges Re≡N–M are almost linear and asymmetric with Re–N = 169.5 pm, Sn–N = 230.1 pm and Re–N–Sn = 164.5° for 1 and Re–N = 168.4 pm, Zr–N = 237.2 pm and Re–N–Zr = 165.6° for 2 . The phosphine ligands at the Re atom are in a meridional arrangement.     

Synthese und Kristallstrukturen von heteronuklearen AgI/FeII‐Koordinationspolymeren: (Me3PhN)2[Ag2Fe(SCN)6], (Me3PhN)6[Ag6Fe3(ECN)18] (E = S,Se) und (Me3PhN)4[Ag2Fe(SCN)8]

The reaction of AgSCN with (Me₃PhN)₃[Fe(NCS)₆] in DMF yields two‐dimensional polymeric, heteronuclear complexes (Me₃PhN)₂[Ag₂Fe(SCN)₆] ( 1 ) and (Me₃PhN)₆[Ag₆Fe₃(SCN)₁₈] · CH₂Cl₂·DMF ( 2a ) with bridging SCN^? ligands, whereas additional (Me₃PhN)(SCN) leads to (Me₃PhN)₄[Ag₂Fe(SCN)₈] ( 3 ) with a one‐dimensional structure. The selenocyanato complex 2b , homologous to 2a , could also be prepared. Single crystal X‐ray structure determinations show, that the Ag⁺ ions in 1 and 2a are coordinated tetrahedrally by four S atoms, in 3 by one N and three S atoms of the bridging SCN^? ligands; six N atoms of the SCN^? or SeCN^? ligands bind to Fe²⁺ in an octahedral arrangement.