332017-79-5Relevant academic research and scientific papers
The crystal structures of PPh4[MCl5(NCMe)] · MeCN (M = Ti, Zr), two modifications of PPh4[TiCl5(NCMe)] and of cis-TiCl4(NCMe)2 · MeCN
Rabe, Susanne,Müller, Ulrich
, p. 201 - 205 (2001)
The title compounds were obtained by reactions of TiCl4 or ZrCl4, respectively, with PPh4Cl and acetonitrile in the presence of S2Cl2. PPh4[TiCl5(NCMe)]·MeCN is unstable and emanates the incorporated acetonitrile. PPh4[TiCl5(NCMe)] forms the two modifications aP114 and mP228, the latter being more stable. The crystal structures were determined by X-ray diffraction. Triclinic PPh4[TiCl5(NCMe)]-(aP114) crystallizes in a distorted variety at the tetragonal AsPh4[RuNCl4] type, i. e. with PPh4+ ions that are piled to columns in the c direction; the [TiCl5(NCMe)]- ions are tilted vs. this direction and thus cause the symmetry reduction from P4/n to P1. PPh4[TiCl5(NCMe)]·MeCN and PPh4[ZrCl5(NCMe)]· MeCN also have the same packing principle as in AsPh4[RuNCl4] with a symmetry reduction from P4/n to P1121/n and a doubled c axis. Instead, PPh4[TiCl5(NCMe)]-(mP228) has a packing with (PPh4+)2 pairs. Orthorhombic TiCl4(NCMe)2·MeCN contains molecules having two acetonitrile ligands attached to the Ti atom in a cis configuration. WILEY-VCH Verlag GmbH, D-69451 Weinheim, 2001.
