Ethyl (E)-3-anilino-2-cyano-3-mercaptoacrylate

In the title compound, C12H12N2O2S, there are S—H⋯N and N—H⋯O hydrogen-bond interactions. The N—H⋯O hydrogen bond is bifurcated, with the hydrogen being simultaneously donated to two equivalent O atoms, forming one intra- and one intermolecular N—H⋯O bond with an R 1 2(4) motif. The motif of the S—H⋯N hydrogen bond is R 2 2(12).

In the title compound, C 12 H 12 N 2 O 2 S, there are S-HÁ Á ÁN and N-HÁ Á ÁO hydrogen-bond interactions. The N-HÁ Á ÁO hydrogen bond is bifurcated, with the hydrogen being simultaneously donated to two equivalent O atoms, forming one intra-and one intermolecular N-HÁ Á ÁO bond with an R 1 2 (4) motif. The motif of the S-HÁ Á ÁN hydrogen bond is R 2 2 (12).

Comment
Acrylics have been studied for many years because of their special chemical properties. They are widely used as elastics, adhesives, covering material and so on. Recent studies have also shown that the derivative of acrylics provide also herbicidal activity (Gao et al., 2006).
It follows from our previous quantum-mechanical study of these compounds that they have several active centres and can easily form polyligand complexes with metals (Xue et al., 2004).
In order to search for new compounds with higher bioactivity, the title compound was synthesized.
The H2A hydrogen is simultaneously donated to two equivalent O atoms, forming one intra-and one intermolecular N-H···O bond with a motif R 1 2 (4) (Etter et al., 1990). A motif of the S-H···N hydrogen bond is R 2 2 (12).

Experimental
The title compound was prepared by the reaction of ethyl 2-cyanoacetate (0.02 mol), KOH (0.03 mol) and N-phenylmethanethioamide (0.02 mol) dissolved in 1,4-dioxane (30 ml) while refluxing about two hours. Yellow single crystals of suitable for X-ray measurements were prisms and they were obtained by recrystallization from ethanol/acetone (1:1 v/v) at room temperature that took about two days. The size of the crystals was about tenths of milimetres in each direction.

Refinement
All the H atoms were discernible in a difference Fourier map. The C-H distances were constrained to 0.93, 0.97 and 0.96 Å for the aryl, methylene and the methyl H atoms, respectively, while U iso (H) = 1.2U eq (C) for the aryls as well as for the methylenes and 1.5U eq (C) for the methyls. The positional parameters as well as the U iso of the H atoms involved in the S-H···N and N-H···O hydrogen bonds were refined freely. Fig. 1. The molecular structure and atom-labelling scheme of the title structure with the displacement ellipsoids drawn at the 30% probability level. as large as those based on F, and R-factors based on ALL data will be even larger.