Preparation, Structure, and Reactivity of Heterometallic Sn-Containing Single- and Double-Cube Derivatives of [Mo₃Se₄(H₂O)₉]⁴⁺ and [W₃Se₄(H₂O)₉]⁴⁺

Abstract

The preparation and properties of Sn-containing derivatives of trinuclear MIV 3Se4 4+ incomplete cuboidal clusters [Mo3Se4(H2O)9]4+ and [W3Se4(H2O)9]4+ are described. Addition of SnII to [Mo3Se4(H2O)9]4+ gives the single-cube [Mo3SnSe4(H2O)12]6+ in 2 M Hpts (pts- = p-toluenesulfonate) and [Mo3(SnCl3)Se4(H2O)9]3+ in 2 M HCl. The structure has been determined by X-ray crystallography on (NH2Me2)6 [Mo3(SnCl3)Se4(NCS)9]·0.5H2O. The reaction of Sn metal with [Mo3Se4(H2O)9]4+ gives the first example of an Se-containing corner-shared double cube, characterized by X-ray crystallography as [Mo6SnSe8(H2O)18](pts)8·2Hpts·28H2O. The clusters [Mo3SnSe4 (H2O)12]6+ and [Mo6SnSe8(H2O)18]8+ are also characterized by the ease of elution in Dowex chromatography, ICP elemental analyses, and the stoichiometries of the oxidation with [Co(dipic)2]-. The preparation of the single-cube [W3SnSe4(H2O)12]6+ in 2 M Hpts, [W3(SnCl3)Se4 (H2O)9]3+ in 2 M HCl, is also described. Conversion of [Mo3SnSe4(H2O)12]6+ into corner-shared double-cubes [Mo6SnSe8 (H2O)18]8+, [Mo6SnSe4S4(H2O)18]8+, [Mo3W3SnSe8(H2O)18]8+, and [Mo3W3SnSe4S4(H2O)18]8+ was achieved by reductive addition of [Mo3Se4(H2O)9]4+, [Mo3S4(H2O)9]4+, [W3Se4(H2O)9]4+, and [W3S4(H2O)9]4+ using BH4 -. A similar procedure was used for the conversion of [W3Se4(H2O)9]4+ into [W6SnSe8(H2O)18]8+. Transfer of SnII is observed in the reaction of [Mo3S4(H2O)9]4+ with [Mo3SnSe4(H2O)12]6+, [W3SnSe4(H2O)12]6+, and [W3SnS4(H2O)12]6+. With the inclusion of similar reactions of [Mo3Se4(H2O)9]4+ etc., the order of affinities for SnII uptake is Mo3S4 4+ > Mo3Se4 4+ > W3Se4 4+ > W3S4 4+. The displacement of InI from [W3InSe4(H2O)12]5+ by SnII is also consistent with equilibrium processes involving dissociation of the heteroatom.

Chalcogenide-bridged cuboidal clusters with M4Q4 (M = Mo, W; Q = S, Se, Te) cores

“…Incomplete cubes ] 4ϩ has been achieved. 33,37 There exist three core types to consider, the single cubes Mo 3 MS 4 (Fig. 5), edged-linked double cubes {Mo 3 MS 4 } 2 (Fig.…”

Preparation, structure and properties of three [MoxW4−xS4(H2O)12]5+ (x = 1–3) and [MoW3Se4(H2O)12]5+ cuboidal complexes alongside [Mo4S4(H2O)12]5+ and [Mo4Se4(H2O)12]5+

“…14 Preparation of [W 3 S 4 (H 2 O) 9 ] 4ϩ and [W 3 Se 4 (H 2 O) 9 ] 4ϩ involved heating the appropriate polymeric compound (1 g) on a steam bath (≈ 90 ЊC) with excess H 3 PO 2 (2 mL; 50% w/w in H 2 O) in concentrated HCl (20 mL) for 15 h. [15][16][17] The product was diluted two-fold and filtered to remove any unreacted solid, diluted to 0.2  HCl and loaded onto a Dowex 50W-X2 cation exchange column, final elution with 2  HCl or 2  Hpts. 18, 19 The purple [W 3 S 4 (H 2 O) 9 ] 4ϩ product was characterised by its UV/VIS absorbance spectrum, 18 peak positions λ/nm (ε/ Ϫ1 cm Ϫ1 per W 3 ) at 317 (6100), 570 (480) in 2  HCl, and 315 (8650), 560 (546) in 2  Hpts. A similar procedure was used to prepare green [W 3 Se 4 (H 2 O) 9 ] 4ϩ characterised by peak positions 359 (6600), 618 nm (547  Ϫ1 cm Ϫ1 ) in 2  Hpts, and 360 (6950), 625 nm (500  Ϫ1 cm Ϫ1 ) in 2  HCl.…”

“…A similar procedure was used to prepare green [W 3 Se 4 (H 2 O) 9 ] 4ϩ characterised by peak positions 359 (6600), 618 nm (547  Ϫ1 cm Ϫ1 ) in 2  Hpts, and 360 (6950), 625 nm (500  Ϫ1 cm Ϫ1 ) in 2  HCl. 18 To prepare [Mo 20 and the Mo 21 in H 2 O (50 mL), as previously described. 22, 23 After addition of further HCl (6 , 80 mL) the solution was heated in a conical flask on a steam bath (≈ 90 ЊC) for 5 h in air.…”

Preparation and properties of the heterometallic cube [Mo3CdS4(H2O)12]4+ and the reaction with H+

“…8, 9 Details of the UV-Vis absorption peak positions are λ/nm (ε/M Ϫ1 cm Ϫ1 per Mo 3 ) 370 (5.0 × 10 3 ), 616 (330) in 2 M HCl and 366 (5.5 × 10 3 ), 603 (360) in 2 M Hpts. 10 Purification and concentration of the product were carried out by Dowex 50W-X2 cation-exchange chromatography using standard procedures.…”