Poly[μ2-aqua-aqua[μ3-N-butyl-N-(2-hydroxyethyl)dithiocarbamato-κ3 O,O′:S]sodium]

The title molecule with empirical formula, [Na(μ3-C6H14ONCS2)(μ2-H2O)(H2O)], contains a triply bridging N-butyl-N-(2-hydroxyethyl)dithiocarbamate anion and forms a two-dimensional polymer.

In the title compound, [Na(C 7 H 14 NOS 2 )(H 2 O) 2 ] n , the Na I cation is coordinated by five O atoms [Na-O = 2.3142 (11)-2.4677 (10) Å ] from three aqua and two N-butyl-N-(2-hydroxyethyl)dithiocarbamate (L) ligands and one S atom [Na-S = 3.0074 (6) Å ] from a third L ligand in a highly distorted octahedral geometry. Two aqua ligands related by an inversion center bridge two Na I cations, and each L ligand coordinates three Na I cations, leading to a layered arrangement aligned parallel to the bc plane. Intermolecular O-HÁ Á ÁS hydrogen bonds are observed in the inner part of each polymeric layer; these are packed along the a axis and held together by weak van der Waals forces.

Chemical context
Dithiocarbamates have recently drawn more attention due to their application in group-transfer radical cyclization reactions (Grainger & Innocenti, 2007) and as ligands for chelating metals (Greenwood & Earnshaw, 1997). In recent years, their applications have not only become apparent as pesticides and fungicides, but they have also been widely used as vulcanization accelerators in the rubber industry (Svetlik et al., 1955). Dithiocarbamates are also of biological importance due to their anticancer, antibacterial, antituberculosis and antifungal properties (Li et al., 2015;Sim et al., 2014;Chauhan et al., 2012;Byrne et al., 2007). Their anti-oxidant properties make them even more valuable compounds. As part of our investigations on organotindithio complexes (Srivastava et al., 2007), we herein report the synthesis and structure of the title compound.

Structural commentary
The title compound is a two-dimensional polymer with formula [Na( 3 -C 7 H 14 NOS 2 )( 2 -H 2 O)(H 2 O)]. Within this ISSN 2056-9890 polymer, each Na I ion exhibits a distorted octahedral geometry ( Fig. 1) made up from coordination by the S atom of one N-butyl-N-(2-hydroxyethyl)dithiocarbamate (L) anion, two hydroxy O atoms from two L ligands and three aqua ligands, of which two aqua ligands form bridging units between two Na I cations. The dithiocarbamate anion acts as a triply bridging ligand, where one S atom coordinates one sodium atom and the O hydroxy atom coordinates two sodium atoms (Fig. 2). The aforementioned feature of multiple coordination modes leads to the formation of polymeric layers parallel to the bc plane with the hydrophobic butyl arms protruding up and down. In the L ligand, while the two S atoms are not chemically equivalent as only one is involved in bonding to the Na cation, the C-S bond lengths are identical at 1.726 (1) Å .

Supramolecular features
Intermolecular O-HÁ Á ÁS hydrogen bonds (Table 1) are observed in the inner part of each polymeric layer (Fig. 3). The layers are further packed along the a axis and held together by weak van der Waals forces.

Figure 3
A portion of the crystal packing showing the O-HÁ Á ÁS hydrogen bonds (dashed lines) in the inner part of the polymeric layer [symmetry codes:

Synthesis and crystallization
The title compound was prepared by the reaction of N-butyl N-hydroxyethyl amine (0.01 mol), carbon disulfide (0.01 mol) and sodium hydroxide (0.01 mol) in dry diethyl ether and was stirred for 4 h at 253 K. The crude product was recrystallized from isopropyl alcohol. It was then dissolved in a hexane:diethyl ether (1:1 v/v) mixture and put in a deep freezer overnight. Square transparent crystals suitable for X ray analysis were obtained in 80% yield (m.p.: 430 K). Analysis calculated for C 7 H 18 NO 3 S 2 (%) S, 29.78; found: S, 29.84.

sup-2
Acta Cryst. (2016). E72, 196-198 Special details Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å 2 )
x y z U iso */U eq Na1 0.44835 (