Bis(tetraphenylphosphonium) tetrasulfidotungstate(VI)

The crystal structure of the title compound, (C24H20P)2[WS4], which was prepared under hydrothermal conditions, contains tetraphenylphosphonium cations linked by supramolecular interactions into chains running along the [110] and [10] directions. The [WS4]2−anions, which lie on twofold axes, are located in the cavities created between the cation chains.

The crystal structure of the title compound, (C 24 H 20 P) 2 [WS 4 ], which was prepared under hydrothermal conditions, contains tetraphenylphosphonium cations linked by supramolecular interactions into chains running along the [110] and [110] directions. The [WS 4 ] 2À anions, which lie on twofold axes, are located in the cavities created between the cation chains.  (1963) and Parvez et al. (1997), respectively. For a review on thiometalates, see Mü ller et al. (1981). Supramolecular interactions between tetraphenylphosphonium cations have been discussed by Dance & Scudder (1995, 1996.

Experimental
Crystal data (C 24

S1. Comment
The ability of tetrathiometallates to act as multidentate ligands has resulted in a rich coordination chemistry, which The [Ph 4 P] + cations are arranged into zigzag chains ( Figure 2) in which each phenyl group points towards another phenyl group in a neighbouring cation, with the H atoms of a given ring oriented towards the π electron density of the second phenyl ring. It has been proposed that attractive interactions between the phenyl groups of [Ph 4 P] + cations play a major role in the crystal packing of compounds of this type (Dance & Scudder, 1995). In particular, the so-called sextuple phenyl embrace, in which three phenyl groups of a [Ph 4 P] + cation face three phenyl groups of an adjacent [Ph 4 P] + cation in an edge-to-face conformation, is a frequently observed supramolecular motif (Dance & Scudder, 1996). As illustrated by Figure 2, the zigzag chains of [Ph 4 P] + cations found in the title compound could be described by considering each [Ph 4 P] + cation to interact with its two neighbours through sextuple phenyl embraces. The P···P distances within the chain are ca 6.5 Å, comparable to those observed in compounds containing this type of chain (Dance & Scudder, 1996) There are relatively short P···P distances, of ca 7.3 Å, between [Ph 4 P] + cations from different chains, which involve two face-to-face phenyl interactions, suggesting that there may be additional interchain supramolecular interactions. This type of interaction has been reported previously (Dance & Scudder,1996), and has been termed quadruple phenyl embrace.
The tetrathiotungstate anions are located in the cavities created between the cation chains ( Figure 3)

S2. Experimental
A mixture of [NH 4 ] 2 [WS 4 ] (0.348 g; 1 mmol) and [Ph 4 P]Br (0.21 g; 0.5 mmol) was loaded into a 23 ml Teflon-lined stainless autoclave, 2 ml of deionized water and 2 ml of ethylenediamine were added to the mixture. After stirring the mixture, the container was closed, heated at 443 K for 4 days, and cooled to room temperature at a cooling rate of 1 K supporting information min -1 . The product was filtered, washed with deionized water, methanol and acetone and dried in air at room temperature.
The product consists of large number of yellow crystals of the title compound (approximately 80% yield).