Novel ion pairs obtained from the reaction of titanium(IV) halides with simple arsane ligands

Abstract

The compounds tert-butylarsenium(III) tri-μ-chlorido-bis[trichloridotitanium(IV)], (C(4)H(12)As)[Ti(2)Cl(9)] or [(t)BuAsH(3)][Ti(2)(μ-Cl)(3)Cl(6)], (II), and bis[bromidotriphenylarsenium(V)] di-μ-bromido-μ-oxido-bis[tribromidotitanium(IV)], (C(18)H(15)AsBr)(2)[Ti(2)Br(8)O] or [Ph(3)AsBr](2)[Ti(2)(μ-O)(μ-Br)(2)Br(6)], (III), were obtained unexpectedly from the reaction of simple arsane ligands with Ti(IV) halides, with (II) lying on a mirror plane in the unit cell of the space group Pbcm. Both compounds contain a completely novel ion, with [(t)BuAsH(3)](+) constituting the first structurally characterized example of a primary arsenium cation. The oxide-bridged titanium-containing [Ti(2)(μ-O)(μ-Br)(2)Br(6)](2-) dianion in (III) is also novel, while the bromidotriphenylarsenium(V) cation is structurally characterized for only the second time.

Titanium, zirconium, hafnium

“…15 [ t BuAsH 3 ][Ti 2 (m-Cl) 3 Cl 6 ] and [Ph 3 AsBr] 2 [Ti 2 (m-O)(m-Br) 2 Br 6 ] were serendipitous products from the reaction of t BuAsH 2 with TiCl 4 and AsPh 3 with TiBr 4 respectively. 16 DFT calculations on the adducts [Cl 3 M-M 0 (PCl 3 ) 4 ] (M = Ti, Zr, Hf; M 0 = Co, Rh, Ir) and the derivatives [R 3 M-M 0 L 4 ] (R = Cl, NH 2 ; L = PCl 3 , PH 3 , CO) indicate that bond strengths in [R 3 M-M 0 L 4 ] depend strongly upon R and L. Steric interactions between Zr and Hf with equatorial PCl 3 groups cause long M-Co bonds in [Cl 3 M-Co(PCl 3 ) 4 ] (M = Zr, Hf). 17 Reaction of TiF 4 and guanidine hydrochloride in EtOH gives the new layered hybrid material [Hgua] 2 Á[Ti 5 O 5 F 12 ].…”

Di-μ-chlorido-bis[dichloridobis(methylamido-κN)bis(methylamine-κN)titanium(IV)]

“…As part of recent work into the synthesis of molecular precursors for the deposition of transition metal pnictide thin films (Potts et al, 2009;Thomas, Blackman et al, 2010;Thomas et al, 2011), we recently reported an unusual ligand-exchange reaction between TiCl 4 and As(NMe 2 ) 3 (Thomas, Pugh et al, 2010). The reaction of one equivalent of As(NMe 2 ) 3 with TiCl 4 did not afford the 1:1 adduct [TiCl 4 {As(NMe 2 ) 3 }].…”

New Ternary Hafniumhalides: Cs[Hf2Br9] and Rb[Hf2Br9]

“…Preparations and properties of different mono‐ and polynuclear compounds have been reported 2–5. In general, these compounds are prepared by dissolving a metal tetrahalide in an organic solvent5,6 or ionic liquid4 in the presence of an organic cation. Compounds with [ M 2 X 9 ] – ‐ or [ M 2 X 10 ] 2– anions ( M = Ti, Zr, or Hf, and X = Cl, Br, or I) are reported in the literature 7–12…”