Synthesis, crystal structure and Hirshfeld analysis of N-ethyl-2-{3-methyl-2-[(2Z)-pent-2-en-1-yl]cyclopent-2-en-1-ylidene}hydrazinecarbothioamide

Abstract

The title compound (C14H23N3S, common name: cis-jasmone 4-ethylthiosemicarbazone) was synthesized by the equimolar reaction of cis-jasmone and 4-ethylthiosemicarbazide in ethanol facilitated by acid catalysis. There is one crystallographically independent molecule in the asymmetric unit, which shows disorder of the terminal ethyl group of the jasmone carbon chain [site-occupancy ratio = 0.911 (5):0.089 (5)]. The thiosemicarbazone entity [N—N—C(=S)—N] is approximately planar, with the maximum deviation of the mean plane through the N/N/C/S/N atoms being 0.0331 (8) Å, while the maximum deviation of the mean plane through the five-membered ring of the jasmone fragment amounts to −0.0337 (8) Å. The dihedral angle between the two planes is 4.98 (7)°. The molecule is not planar due to this structural feature and the sp 3-hybridized atoms of the jasmone carbon chain. Additionally, one H...N intramolecular interaction is observed, with graph-set motif S(5). In the crystal, the molecules are connected through pairs of H...S interactions with R 2 2(8) and R 2 1(7) graph-set motifs into centrosymmetric dimers. The dimers are further connected by H...N interactions with graph-set motif R 2 2(12), which are related by an inversion centre, forming a mono-periodic hydrogen-bonded ribbon parallel to the b-axis. The crystal structure and the supramolecular assembly of the title compound are compared with four known cis-jasmone thiosemicarbazone derivatives (two crystalline modifications of the non-substituted form, the 4-methyl and the 4-phenyl derivatives). A Hirshfeld surface analysis indicates that the major contributions for the crystal cohesion are from H...H (70.7%), H...S/S...H (13.5%), H...C/C...H (8.8%), and H...N/N...H (6.6%) interfaces (only the disordered atoms with the highest s.o.f. were considered for the evaluation).