Abstract
C 18 H 16 N 10 O 2 Zn, triclinic, P1 (no. 2), a = 10.218(7) Å, b = 10.490(7) Å, c = 11.101(8) Å, α = 79.590(11)°, β = 65.913(12)°, γ = 66.785(10)°, V = 998.0(12) Å 3 , Z = 2, Rgt(F) = 0.0516, wR ref (F 2 ) = 0.1323, T = 293(2) K.

methanol (20 mL). The reaction mixture was refluxed for 1 h and cooled to room temperature. Then zinc(II) acetate dihydrate (0.110 g, 0.5 mmol) was added. After stirring for 1 h, the mixture was filtered and set aside to crystallize for several days, giving yellow block crystals.
Experimental details
The structure was solved by direct methods and refined with the SHELX crystallographic software package [3] . The hydrogen atoms were placed at calculated positions and refined as riding atoms with isotropic displacement parameters.
Discussion
Hydrazones derived from 2-aceto-pyrazine and their metal complexes have been widely investigated mainly due to their excellent biological activities [4] [5] [6] . However, most research has focused on aryl-hydrazones and investigations on alkylhydrazones are relatively few [4] [5] [6] [7] . Herein, the title complex was synthesized and characterized by X-ray diffraction in this work.
Discussion
In the title crystal structure, the central Zn(II) ion is sixcoordinated to two anionic hydrazone ligands by a pair of ON 2 donor sets, thus giving a distorted octahedral coordination geometry. The C-O bond of the hydrazone ligand is in the enolate form, which is supported by the distance of C-O bond being 1.264(5)/1.263(5) Å for C16-O2 and C7-O1, respectively, similar to what was found in other hydrazone ligands [6, 7] . The structure is similar to that of the Zn(II) complex with the 2-aceto-pyrazine benzoylhydrazone ligand [6] . As expected, there exist no classical hydrogen bonds in the crystal.

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