Über die Reaktionen von N-Chloracetonimin mit Molybdänpentachlorid und Wolframhexachlorid Die Kristallstruktur von Me2CNH2[MoOCl4]

Reactions of N-Chloroacetoneimine with Molybdenum Pentachloride and Tungsten Hexachloride. Crystal Structure of Me₂C?NH₂[MoOCl₄] WCl₆ reacts with N-chloroacetoneimine under elimination of chlorine and formation of pentachloro-isopropylideneimino-tungsten(VI), Cl₅W?N?CMe₂, a brown-black crystal powder, which was characterized by i.r. spectroscopy. MoCl₅ reacts in a similar way, although only a product mixture can be obtained. Partial hydrolysis of this mixture yields isopropylideneiminium-tetrachlorooxomolybdate(V), Me₂C?NH₂⁺[MoOCl₄]^?, of which the crystal structure was determined (2323 unique observed reflexions, R = 0.049). Space group P2₁/c, Z = 4, a = 878.6, b = 907.2, c = 1252.2 pm, β = 91.29°. The compound consists of Me₂C?NH₂⁺ ions with a planar arrangement of the skeletal atoms and a CN bond length of 126.7 pm and of dimeric, centrosymmetric anions [MoOCl₄]₂^2? having Mo atoms linked via asymmetric chloro bridges (MoCl distances 238.4 and 307.6 pm). The longer Mo? Cl contacts are located in the trans-positions of the terminal oxoligands (MoO distance 164 pm).