Phosphaniminato‐Komplexe von Bismut(III). Die Kristallstrukturen von [BiF2(NPEt3)(HNPEt3)]2 und [Bi2I(NPPh3)4]I3

Phosphoraneiminato Complexes of Bismuth(III). Crystal Structures of [BiF₂(NPEt₃)(HNPEt₃)]₂ and [Bi₂I(NPPh₃)₄]I₃ [BiF₂(NPEt₃)(HNPEt₃)]₂ ( 1 ) has been obtained by the reaction of BiF₃ with Me₃SiNPEt₃ at 100 °C and subsequent extraction with 1,2‐dimethoxyethane in the presence of traces of water forming pale‐yellow, moisture sensitive crystals, which were characterized by a crystal structure determination. Space group P2₁/n, Z = 4, lattice dimensions at –83 °C: a = 2105.0, b = 1195.8, c = 728.2 pm, β = 92.55°. 1  forms centrosymmetric dimeric molecules, in which the Bi atoms are linked via Bi–N bonds of varying length (213.9 and 240.1 pm) of the NPEt₃^– groups to form a Bi₂N₂ four‐membered ring. The longer one of the two Bi–N bonds is trans to one terminal F atom. [Bi₂I(NPPh₃)₄]I₃ ( 2 ) has been obtained by the reaction of bismuth with N‐iodine triphenylphosphaneimine in dichloromethane forming red crystals. Crystal structure determination of 2 · 2.5 CH₂Cl₂: Space group P2₁/n, Z = 4, lattice dimensions at –50 °C: a = 1542.6, b = 2409.1, c = 2173.5 pm, β = 105.82°. In 2 the Bi atoms are linked via two N atoms of two NPPh₃^– groups to form a non‐planar Bi₂N₂ four‐membered ring with a fold angle of 27° along the N…N connection line. The two remaining NPPh₃^– groups are terminally connected and bent in the same direction. The iodide ion caps the two Bi atoms so that a [Bi₂I(NPPh₃)₄]⁺ cation is formed.     

The Crystal Structures of a Lower Order and a “Higher Order” Cyanocuprate: [tBuCu(CN)Li(OEt2)2]∞ and [tBuCutBu{Li(thf)(pmdeta)}2CN]

Different types of bonding are present in cyanocuprates 1 and 2 , whose crystal structures could be determined (the drawings below show the important structural characteristics). Accordingly, 1 is a lower order cyanocuprate of the type RCu(CN)Li, whereas 2 , which is of the type R₂Cu(CN)Li₂, does not exist as a “higher order” cyanocuprate with Cu–CN bonds, but rather as a cyano-Gilman cuprate.     

Synthese eines Titana-Oxacyclohexanringes durch kontrollierte Ringöffnung von Tetrahydrofuran. Kristallstrukturen von [Ti(CH2)4O{Me2Si(NBut)2}]2, [TiCl{Me2Si(NBut)2}]3(μ3-O)(μ3-Cl) und [Li2(THF)3{Me2Si(NBut)2}]

Synthesis of a Titana-Oxacyclohexane Ring by Controlled Ring Opening of Tetrahydrofurane. Crystal Structures of [Ti(CH₂)₄O{Me₂Si(NBu^t)₂}]₂, [TiCl{Me₂Si(NBu^t)₂}]₃(μ₃-O)(μ₃-Cl), and [Li₂(THF)₃{Me₂Si(NBu^t)₂}] [TiCl₃(THF)₃] reacts with [(Bu^tNLi)₂SiMe₂]₂ in diethyl ether at –35 °C under redox disproportionation and formation of the yellow titana(IV)-oxacyclohexane complex [Ti(CH₂)₄O{Me₂Si(NBu^t)₂}]₂. According to the crystal structure analysis the titanium atoms are linked to form centrosymmetric dimers via the oxygen atoms of the Ti(CH₂)₄O six-membered rings, which are in chair conformation. Along with the nitrogen atoms of the chelating [Me₂Si(NBu^t)₂]^2– ligands the titanium atoms obtain a distorted trigonal-bipyramidal surrounding. While [TiCl{Me₂Si(NBu^t)₂}]₃(μ₃-O)(μ₃-Cl) with a cluster-like structure is obtained as a by-product. According to the crystal structure analysis of [Li₂(THF)₃ · {Me₂Si(NBu^t)₂}], which is involved in the synthesis reaction, the two lithium atoms are connected with both the nitrogen atoms of the t-butyl amide groups and bridged via an oxygen atom of one of the THF molecules.     

Synthese und Kristallstrukturen der Phosphanimin-Komplexe [Cu(μ-HNPEt3)]4(O3S–CF3)4 und [Pt2Me6(μ-I)2(μ-HNPMe3)]

Synthesis and Crystal Structures of the Phosphaneimine Complexes [Cu(μ-HNPEt₃)]₄(O₃S–CF₃)₄ and [Pt₂Me₆(μ-I)₂(μ-HNPMe₃)] The title compounds have been prepared by the reaction of copper(I)triflate with [NiBr(NPEt₃)]₄ in CH₂Cl₂ suspension in the presence of water, and by the reaction of [PtMe₃I]₄ with Me₃SiNPMe₃ in boiling toluene in the presence of cesium fluoride, respectively. According to the crystal structure determinations the cation of the copper complex forms tetrameric units [Cu(HNPEt₃)]₄⁴⁺ with S₄ symmetry with Cu–N bond lengths of 191.6 and 192.1 pm. In the platinum complex the platinum atoms are linked by two μ-I bridging atoms as well as by the μ-N atom of the HNPMe₃ ligand with Pt–N bond lengths of 228.1 and 229.5 pm.     

Phosphaniminato-Komplexe des Zinks mit Hydrido-, Alkinylo-, Alkenylo- und Amido-Liganden

Phosphoraneiminato Complexes of Zinc with Hydrido, Alkynylo, Alkenylo, and Amido Ligands Synthesis and properties of the phosphoraneiminato complexes [ZnCl(NPMe₃)]₄ ( 1 ), [ZnH(NPMe₃)]₄ ( 2 ) as well as of the alkynylo derivatives [Zn(C≡C–SiMe₃)(NPMe₃)]₄ ( 3 ), [Zn(C≡C–C≡C–SiMe₃)(NPR₃)]₄ [R = Me ( 4 a ), R = Et ( 4 b )], [Zn(C≡C–Ph)(NPMe₃)]₄ ( 5 ) and of the alkenylozinc complexes [Zn(CH=CHMe)(NPR₃)]₄ [R = Me ( 6 a ), R = Et ( 6 b )] are described. According to crystal structure analyses of 1 , 3 , and 4 b these complexes possess heterocubane structures with only slightly distorted Zn₄N₄ cubic skeletons. Experiments to substitute the terminal ligands at the zinc atoms by bis(trimethylsilyl)amido groups lead to disintegration of the heterocubanes and formation of the dimeric complex [Zn(μ₂-NPEt₃){N(SiMe₃)₂}]₂ ( 7 ) and of the trinuclear derivative [Zn₃(μ₂-NPMe₃)₄{N(SiMe₃)₂}₂] ( 8 ), in which the central zinc atom is surrounded by the four N atoms of the NPEt₃^– groups in a spiro-cyclic fashion. 7 and 8 are also characterized by crystal structure analyses.     

Die Kristallstrukturen der Triarylzinkate [Mg2Br3(THF)6][ZnPh3] und [MgBr(THF)5][ZnMes3]

Crystal Structures of the Triarylzincates [Mg₂Br₃(THF)₆][ZnPh₃] and [MgBr(THF)₅][ZnMes₃] The title compounds were obtained from reactions of the phosphoraneiminato complex [ZnBr(NPMe₃)]₄ with excess Grignard reagents RMgBr (R = C₆H₅, 2,4,6-(CH₃)₃–C₆H₂) in THF solution. According to X-ray structure determinations the [ZnR₃]^– ions contain zinc atoms which are coordinated in a planar fashion with Zn–C distances of 200.7 pm (R = Ph) and 203.4 pm (R = Mes) in average.     

Die Reaktionen von Europium und Yttrium mit N‐Iod‐triphenylphosphanimin. Kristallstrukturen von [EuI2(DME)3], [Eu2I(NPPh3)5(DME)] und [Y2I(NPPh3)4(THF)4]+I3–

The Reactions of Europium and Yttrium with N‐Iodinetriphenylphosphoraneimine. Crystal Structures of [EuI₂(DME)₃], [Eu₂I(NPPh₃)₅(DME)] and [Y₂I(NPPh₃)₄(THF)₄]⁺I₃^– When treated with ultrasound, the reaction of europium metal with INPPh₃ in 1,2‐dimethoxyethane (DME) leads to the complexes [EuI₂(DME)₃] ( 1 ) and [Eu₂I(NPPh₃)₅(DME)] ( 2 ) which are separated from each other by fractional crystallization. On the other hand, the reaction of yttrium metal with INPPh₃ under similar conditions in THF gives the ionic phosphoraneiminato complex [Y₂I(NPPh₃)₄(THF)₄]⁺I₃^– ( 3 ). All complexes are characterized by crystal structure determinations. 1 : Space group P2₁, Z = 2, lattice dimensions at 188 K: a = 848.9(1); b = 1059.4(1); c = 1227.9(1) pm; β = 93.793(6)°; R = 0.0246. In the molecular structure of 1 the europium atom is eightfold coordinated with a bond angle I–Eu–I of 158.51°. 2 · 2 DME: Space group P1, Z = 2, lattice dimensions at 193 K: a = 1405.5(1); b = 1652.2(2); c = 2203.7(2) pm; α = 89.404(11)°; β = 72.958(11)°; γ = 78.657(11)°; R = 0.0391. In 2 the europium atoms are linked by the μ‐N‐atoms of two (NPPh₃^–) groups to form a planar Eu₂N₂ four‐membered ring. One of the Eu atoms is terminally coordinated by the N atoms of two (NPPh₃^–) groups, thus achieving a distorted tetrahedral surrounding. The second Eu atom is coordinated by the N atom of one (NPPh₃^–) group, by the terminally bounded iodine atom and by the oxygen atoms of the DME chelate, thus achieving a distorted octahedral surrounding. 3 · 6¹/₂ THF: Space group P1, Z = 2, lattice dimensions at 103 K: a = 1739.7(2); b = 1770.1(2); c = 2153.8(3) pm; α = 74.929(15)°; β = 84.223(14)°; γ = 64.612(12)°; R = 0.0638. In the cation [Y₂I(NPPh₃)₄(THF)₄]⁺ of 3 the yttrium atoms are linked by the μ‐N atoms of two (NPPh₃^–) groups as well as by the μ‐I atom. One (NPPh₃^–) ligand and two THF molecules complete the distorted octahedral coordination at each yttrium atom.