(Bu4N)[Re{NB(C6F5)3}Cl4(OH2)] - Struktur und EPR-Spektren

Terminal nitride complexes of rhenium, osmium and molybdenum can form complexes with either alkylating agents, Lewis acidic metal halides, or low-valent, coordinatively unsaturated metal complexes. [1][2][3][4][5][6][7] The few reactions of this type with a first-row transition-metal complex are limited to vanadium. [8,9] Recently, the nitride chemistry of the chromium(V) cation has been significantly expanded by introduction of a preparative route which is based on nitrogen transfer from [Mn(N)(salen)] (salen = N,N'-bis(salicylidene)ethylenediamine) to the chromium(V) cation. [10][11][12] With a range of chromium nitride complexes at hand we have investigated their reactivity and found that nucleophilicity is a general property which can be observed during formation of imide complexes with, for example, the trityl cation, tris-(pentafluorophenyl)boron, and methyl triflate. In addition we report that terminal chromium(V) nitride complexes coordinate through the nitride ligand to low-valent complexes of the platinum metals. These compounds are possible precursors to bimetallic nitride phases which are gaining in importance as heterogeneous catalysts in, for example, the Haber-Bosch process. [13] Solutions of terminal chromium nitride complexes in noncoordinating solvents treated with electrophiles such as B(C 6 F 5 ) 3 or C(C 6 H 5 ) 3 + quickly yield intensely colored orangered or green solutions. The reactions proceed cleanly as shown by EPR spectra which display a signal from a single S = 1 = 2 spin species. Similar reactivity was observed in reactions with either [Rh(cod)Cl] 2 or cis-[PtCl 2 (dmso) 2 ] (cod = 1,5-cyclooctadiene, dmso = dimethyl sulfoxide). Structures of some of these systems, characterized by single-crystal X-ray diffraction, are shown in Scheme 1.Experimental and crystallographic details such as ORTEP drawings and metric parameters of complexes 1-5 (Scheme 1) are available in the Supporting Information (Tables S1 and S1 a). Inspection of the structures reveals a number of general aspects: there is a strong propensity for the chromium center to increase its coordination number from five to six upon coordination of the nitride ligand. This propensity is expected and a consequence of the trans influence of either an imide or a bridging nitride ligand which is significantly lower than that of a terminal nitride ligand. Accompanying this, the displacement of Cr out of the plane spanned by the equatorial ligators is diminished from about 0.5 to about 0.2 . The Cr À N bond length is elongated from 1.55 in the terminal nitride complexes to approximately 1.60-1.62 in the functionalized systems. Comparison of structure 1 with that of [Cr(N)-(salen)] reveals that the metal-salen ligand bonds are significantly shorter when the nitride ligand is functionalized, as expected when two ligands compete for electron donation. However, for the systems derived from [Cr(N)(dbm) 2 ] the situation is less clear (dbm = dibenzoylmethanolate). In complex 2 all the Cr-dbm bonds are longer than in the parent terminal nit...

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mentioning

confidence: 99%

Heterobimetallic Nitride Complexes from Terminal Chromium(V) Nitride Complexes: Hyperfine Coupling Increases with Distance

et al. 2011

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“…Die ausgebildeten Nitridobru È cken sind nahezu linear. Die Herabsetzung des trans-Einflusses des mehrfachgebundenen Stickstoff-Liganden kann bei Komplexen mit der Koordinationszahl 5 zu einer Besetzung der vakanten sechsten Koordinationsposition fu È hren [9,12,13]. Die Rhenium±Stickstoff-Mehrfachbindungen werden durch die Addition des Borans nur geringfu È gig (maximal 0,03 A Ê ) verla È ngert.…”

Section: The Reaction Of Dichlorophenylborane With Nitrido Complexes unclassified

Zur Reaktion von Dichlorphenylboran mit Nitridokomplexen des Rheniums

Abram

Hagenbach

Voigt

et al. 2001

Z. anorg. allg. Chem.

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Professor Kurt Dehnicke zum 70. Geburtstag gewidmet Inhaltsu È bersicht. BCl 2 Ph reagiert mit terminalen Nitridoliganden von Rheniumkomplexen unter Ausbildung einer Stickstoffbru È cke zwischen dem Ûbergangsmetall und Bor. Wie Strukturuntersuchungen an den Komplexen [Re(NBCl 2 Ph)Cl 2 (Ph 3 P) 2 ], [Re(NBCl 2 Ph)Cl 2 (Me 2 PhP) 3 ], [Re(NBCl 2 Ph)Cl(Me 2 PhP) 2 (Et 2 dtc)] und [Re(NBCl 2 Ph)-(Me 2 PhP)(Et 2 dtc) 2 ] (Et 2 dtc ± = N,N'-Diethyldithiocarbamat) zeigen, verla È ngert sich die Rhenium±Stickstoff-Mehrfachbindung infolge der Ausbildung der Re±N±B-Bru È cke nur geringfu È gig, wa È hrend eine deutliche Abnahme des trans-Einflusses des Nitridoliganden zu verzeichnen ist. Komplexe des Typs [Re(NBCl 2 Ph)Cl 4 (Y)] ± (Y = Cl oder Lo È sungsmittel) entstehen wa È hrend der Reaktion von [ReNCl 4 ] ± mit BCl 2 Ph und ko È nnen EPR-spektroskopisch nachgewiesen werden. Ausgehend von [ReNBr 4 ] ± oder [ReN(NCS) 5 ] 2± la È uft neben der Ausbildung der Nitridobru È kken ein Ligandenaustausch in der a È quatorialen Koordinationsspha È re mit freigesetzten Cl ± -Liganden ab. In den Reaktionsmischungen lassen sich Komplexe mit gemischter Cl ± /Br ± (oder NCS ± )-Koordinationsspha È re anhand ihrer EPR-Spektren identifizieren.Abstract. BCl 2 Ph reacts with terminal nitrido ligands of rhenium complexes under formation of a nitrogen bridge between the transition metal and boron. Structural studies on [Re(NBCl 2 Ph)Cl 2 (Ph 3 P) 2 ], [Re(NBCl 2 Ph)Cl 2 (Me 2 PhP) 3 ], [Re(NBCl 2 Ph)Cl(Me 2 PhP) 2 (Et 2 dtc)] and [Re(NBCl 2 Ph)-(Me 2 PhP)(Et 2 dtc) 2 ] (Et 2 dtc ± = N,N'-diethyldithiocarbamate) demonstrate that the rhenium-nitrogen bond is only slightly lengthened upon the formation of the nitrido bridge whereas a significant decrease of the structural trans influence of the nitrido ligand is observed.[Re(NBCl 2 Ph)Cl 4 (Y)] ± (Y = Cl or solvent) complexes are formed during the reaction of [ReNCl 4 ] ± with BCl 2 Ph. The rhenium(VI) compounds (d 1 configuration) can easily be detected by EPR spectroscopy. The formation of {Re(NBCl 2 Ph)} complexes with mixed Cl ± /Br ± (or NCS ± ) coordination spheres is evident when the reactions start from [ReNBr 4 ] ± or [ReN(NCS) 5 ] 2± which can be derived from the EPR spectra of the reaction mixtures.

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Reactive Transition Metal Nitride Complexes

Smith

2014

Progress in Inorganic Chemistry

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(Bu4N)[Re{NB(C6F5)3}Cl4(OH2)] - Struktur und EPR-Spektren

Cited by 18 publications

References 4 publications

Heterobimetallic Nitride Complexes from Terminal Chromium(V) Nitride Complexes: Hyperfine Coupling Increases with Distance

Heterobimetallic Nitride Complexes from Terminal Chromium(V) Nitride Complexes: Hyperfine Coupling Increases with Distance

Zur Reaktion von Dichlorphenylboran mit Nitridokomplexen des Rheniums

Reactive Transition Metal Nitride Complexes

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