Über Metall‐Stickoxid‐Komplexe. XV. Über das komplexchemische Verhalten der Nitrosyleisenhalogenide

Abstract

Die dimeren Dinitrosyl‐ und die monomeren Trinitrosyleisenhalogenide, [Fe(NO)2X]2 bzw. Pe(NO)3X (X = Halogen) reagieren bei Raumtemperatur in Lösung mit Organylen des Phosphors und seiner Homologen, sowie mit verschiedenen N‐Basen unter Bildung einkerniger, paramagnetischer Verbindungen des Typs Fe(NO)2LX (L = Ligand). Mit Dianilinoäthan entsteht ein polarer Komplex [Fe(NO)2(C6H5NH · C2H4 · NHC6H5)]+Br−. Dielektrische und magnetische Messungen erlauben nähere Aussagen über die Struktur der Verbindungen. Die Umsetzung von Dinitrosyleisenbromid mit geschmolzenem Triphenylphosphin ergibt unter Valenzdisproportionierung die Verbindungen Fe(NO)(P(C6H5)3)2Br2 und Fe(NO)2 (P(C6H5)3)2. Die Dinitrosylverbindungen Fe(NO)2L2 (L  P(C6H5)3, P(C6H11)3) entstehen auch durch Reduktion der Phosphin‐dinitrosyleisenhalogenide mit Natriumamalgam bei Anwesenheit des betreffenden Phosphins; Bis‐[triphenylarsin]‐dinitrosyleisen hingegen bildet sich nur aus der Monosubstitutionsverbindung Fe(NO)2(CO)As(C6H5)3 mit Triphenylarsin.

Darstellung und Reaktionen von Dichlorotrinitrosylvanadin

“…Intensive Absorptionen sind auch im Bereich der Y V -C1-Schwingungen zu beobachten. Wie der Vergleich der monomeren Nitrosylchloride von Chrom [6], Eisen und Kobalt [7] mit dem chlorverbriickten [CO(NO)~C~], [S] zeigt, lassen sich…”

Facile synthesis of Fe(NO)2L2 compounds, where L=phosphines and phosphites

“…It seems likely that the phosphines themselves serve as the reducing agents in these reactions. Heiber and Kramolovsky [11] reported the synthesis of Fe(NO) 2 (PR 3 ) 2 derivatives by fusing [Fe(NO) 2 (l-X)] 2 reagents with the appropriate phosphines.…”

Polyhedral Interconversion Coupled with Proton Transfer between an Ammonium Cation and the [Co(CO)4]− Ion

“…The structures analyzed by Brammer et al correspond to compounds with NÀH···Co hydrogen bonds, a behavior consistent with the acidity of the hydrido carbonyl complex in water. [3] According to the structure-correlation principle, the variety of H···Co distances found (between 2.63 for a NÀH···Co hydrogen-bonded species and 1.43 for the hydrido complex) should correspond to snapshots along the proton-transfer reaction coordinate. Since the coordination spheres of both the N and Co atoms are significantly affected by the progress of the protontransfer reaction, these systems provide an excellent opportunity to test the applicability of the polyhedral-shape measures as reaction coordinates and to correlate the potential-energy surface with the structural evolution.…”

“…Therefore, the aim of this communication is to show how DFT calculations provide an energy profile for such a reaction that accounts for the fine details of the distribution of structures along the path and how the proton transfer is coupled to changes in the coordination polyhedra of the N and Co atoms. An outcome of this study is that the energy and the stereochemical changes that accompany the proton transfer can be described as a function of a single parameter, the generalized polyhedral-interconversion coordinate [4] for the transformation of a [CoL(CO) 3 ] À (L = ligand) tetrahedron into a vacant trigonal bipyramid.…”

“…Changes in bond distances and angles and the potential energy of the system can be adequately described by this reaction coordinate. The geometries of experimental structures of families of compounds with the general formulae [Co(CO) 4 ] À , [Co-(PR 3 )(CO) 3 ] À , [CoH(CO) 4 ], [CoH(PR 3 )(CO) 3 ], and [CoH-(PR 3 ) 4 ] offer snapshots of the low-energy regions of the potential-energy surface for the proton-transfer reaction in the gas phase. Furthermore, there is a good correspondence between the optimized structures of the species that participate in this reaction and those found experimentally, thus providing an excellent illustration of the structure-correlation principle.…”