(2,2′-Bipyridyl-κ2 N,N′)bis(N-butyl-N-methyldithiocarbamato-κ2 S,S′)cadmium(II)

The CdII atom in the title compound, [Cd(C6H12NS2)2(C10H8N2)], is hexacoordinated by two dithiocarbamate ligands and the N atoms from a bidentate 2,2′-bipyridyl molecule. The coordination geometry is based on a distorted trigonal–prismatic arrangement of the N2S4 donor set. Supramolecular chains, aligned along the a-axis direction, are mediated by C—H⋯S interactions and these are connected into layers that stack along the c axis via π–π interactions [Cg(pyridyl)⋯Cg(pyridyl) = 3.6587 (13) Å].

The Cd II atom in the title compound, [Cd(C 6 H 12 NS 2 ) 2 -(C 10 H 8 N 2 )], is hexacoordinated by two dithiocarbamate ligands and the N atoms from a bidentate 2,2 0 -bipyridyl molecule. The coordination geometry is based on a distorted trigonal-prismatic arrangement of the N 2 S 4 donor set. Supramolecular chains, aligned along the a-axis direction, are mediated by C-HÁ Á ÁS interactions and these are connected into layers that stack along the c axis viainteractions [Cg(pyridyl)Á Á ÁCg(pyridyl) = 3.6587 (13) Å ].
between trigonal prismatic and octahedral with a leaning towards the former. The angle between the triangular faces defined by the S1,S3,N4 and S2,S4,N3 atoms is 5.36 (9) °, and these are twisted by approximately 13 ° about the axis through them, compared to 0 ° for an an ideal trigonal prism and 60 ° for an ideal octahedron. The symmetric mode of coordination of the dithiocarbamate ligands is reflected in the associated C≐S bond distances which lie in the narrow range of 1.721 (2) Linear supramolecular chains along the a axis are formed in the crystal structure via C-H···S interactions, Table   2 and Fig. 2. These are consolidated into layers in the ab plane by π-π interactions formed between the pyridyl rings [Cg(N3,C14-C18)···Cg(N4,C19-C23) i = 3.6587 (13) Å with angle between rings = 5.35 (11) ° for i: 2 -x, 1 -y, 1 -z].
Supramolecular layers stack along the c axis, Fig. 3.

Experimental
The title compound was prepared using an in situ method. The first step was the addition of carbon disulfide (0.03 mol) to an ethanolic solution (20 ml) of butylmethylamine (0.03 mol) in ethanol (20 ml). The mixture was stirred for 1 h at 277 K.
The resulting solution was added drop wise to a solution of cadmium(II) dichloride (0.015 mol) in ethanol (20 ml) followed by stirring for 4 h. A white precipitate was formed, filtered and washed with cold ethanol. The precipitate, Cd(C 6 H 12 NS 2 ) 2 (0.01 mol), and 2,2'-bipyridyl (0.01 mol) were dissolved together in chloroform (20 ml) and stirred for 1 h. A yellowish precipitate was formed, filtered and dried in a desiccator. Crystallization was from its ethanol:chloroform (1:2) solution.

Refinement
Carbon-bound H-atoms were placed in calculated positions (C-H 0.95 to 0.99 Å) and were included in the refinement in the riding model approximation, with U iso (H) set to 1.2 to 1.5U equiv (C). Fig. 1. The molecular structure of (I) showing the atom-labelling scheme and displacement ellipsoids at the 50% probability level.  (

Special details
Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > 2σ(F 2 ) is used only for calculating Rfactors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.