Darstellung, IR-Spektrum und Kristallstruktur von [WNCI₃ P0Cl₃]₄ 2 POCI₃ / Preparation, IR Spectra and Crystal Structure of [WNCl₃ • P0Cl₃]₄ • 2 P0Cl₃

Abstract

Abstract Tungsten nitride chloride-POCl 3 solvate, [WNCl 3 • POCl 3 ] 4 • 2 POCl 3 is prepared by the reaction of WNCI 3 with excess POCI 3 . With equimolar amounts of POCI 3 in dichloromethane suspension the complex [WNCI 3 • POCl 3 ] 4 • 2 CH 2 CI 2 is formed, which is easily decomposed leaving pure [WNCI 3 • POCl 3 ] 4 . The IR spectra of these complexes were recorded and assigned. A new preparative route to WNCI3 from tungsten hexachloride and iodine azide is described. [WNCI 3 • POCl 3 ] 4 • 2 POCl 3 crystallizes in the triclinic space group P1̅ with two tetrameric units per unit cell. The crystal structure was solved by X-ray diffraction methods (Å = 0,087; 3085 observed reflexions). The structure consists of planar and almost square W 4 N 4 -eight-membered rings with alternating W-N bond lengths. The distorted octahedral environment of the tungsten atoms is completed by three terminal Cl-ligands and by the oxygen atom of a POCI 3 molecule, which is coordinated trans to the W = N triple bond. The two additional POCI 3 molecules are weakly linked to two of the four POCI 3 solvate molecules, giving rise to an increase of the W-O bond lengths to these donor groups