Synthesis, characterization, crystal structure and supra-molecularity of ethyl (E)-2-cyano-3-(3-methyl-thio-phen-2-yl)acrylate and a new polymorph of ethyl (E)-2-cyano-3-(thio-phen-2-yl)acrylate

Mahmoud Al-Refai; Basem F Ali; Ala'a B Said; Armin Geyer; Michael Marsch; Klaus Harms

doi:10.1107/S2056989019011435

Synthesis, characterization, crystal structure and supra-molecularity of ethyl (E)-2-cyano-3-(3-methyl-thio-phen-2-yl)acrylate and a new polymorph of ethyl (E)-2-cyano-3-(thio-phen-2-yl)acrylate

Acta Crystallogr E Crystallogr Commun. 2019 Aug 23;75(Pt 9):1357-1361. doi: 10.1107/S2056989019011435. eCollection 2019 Sep 1.

Authors

Mahmoud Al-Refai¹, Basem F Ali¹, Ala'a B Said¹, Armin Geyer², Michael Marsch², Klaus Harms²

Affiliations

¹ Department of Chemistry, Al al-Bayt University, Mafraq 25113, Jordan.
² Faculty of Chemistry, Philipps University Marburg, Hans-Meerwein-Strasse 4, 35032 Marburg, Germany.

Abstract

The synthesis, crystal structure and structural motif of two thio-phene-based cyano-acrylate derivatives, namely, ethyl (E)-2-cyano-3-(3-methyl-thio-phen-2-yl)acrylate (1), C₁₁H₁₁NO₂S, and ethyl (E)-2-cyano-3-(thio-phen-2-yl)acrylate (2), C₁₀H₉NO₂S, are reported. Derivative 1 crystallized with two independent molecules in the asymmetric unit, and derivative 2 represents a new monoclinic (C2/m) polymorph. The mol-ecular conformations of 1 and the two polymorphs of 2 are very similar, as all non-H atoms are planar except for the methyl of the ethyl groups. The inter-molecular inter-actions and crystal packing of 1 and 2 are described and compared with that of the reported monoclinic (C2/m) polymorph of derivative 2 [Castro Agudelo et al. (2017 ▸). Acta Cryst. E73, 1287-1289].

Keywords: crystal structure; crystal supramolecularity; polymorph; thiophene-based cyanoacrylates.

Grants and funding

This work was funded by Al al-Bayt University grant . Deutsche Forschungsgemeinschaft grant .