The synthesis, spectroscopic data and crystal and molecular structures of four 3-(3-phenylprop-1-ene-3-one-1-yl)thiophene derivatives, namely 1-(4-hydroxyphenyl)-3-(thiophen-3-yl)prop-1-en-3-one, C13H10O2S, (1), 1-(4-methoxyphenyl)-3-(thiophen-3-yl)prop-1-en-3-one, C14H12O2S, (2), 1-(4-ethoxyphenyl)-3-(thiophen-3-yl)prop-1-en-3-one, C15H14O2S, (3), and 1-(4-bromophenyl)-3-(thiophen-3-yl)prop-1-en-3-one, C13H9BrOS, (4), are described. The four chalcones have been synthesized by reaction of thiophene-3-carbaldehyde with an acetophenone derivative in an absolute ethanol solution containing potassium hydroxide, and differ in the substituent at the para position of the phenyl ring: –OH for 1, –OCH3 for 2, –OCH2CH3 for 3 and –Br for 4. The thiophene ring in 4 was found to be disordered over two orientations with occupancies 0.702 (4) and 0.298 (4). The configuration about the C=C bond is E. The thiophene and phenyl rings are inclined by 4.73 (12) for 1, 12.36 (11) for 2, 17.44 (11) for 3 and 46.1 (6) and 48.6 (6)° for 4, indicating that the –OH derivative is almost planar and the –Br derivative deviates the most from planarity. However, the substituent has no real influence on the bond distances in the α,β-unsaturated carbonyl moiety. The molecular packing of 1 features chain formation in the a-axis direction by O—H...O contacts. In the case of 2 and 3, the packing is characterized by dimer formation through C—H...O interactions. In addition, C—H...π(thiophene) interactions in 2 and C—H...S(thiophene) interactions in 3 contribute to the three-dimensional architecture. The presence of C—H...π(thiophene) contacts in the crystal of 4 results in chain formation in the c-axis direction. The Hirshfeld surface analysis shows that for all four derivatives, the highest contribution to surface contacts arises from contacts in which H atoms are involved.

The content of this paper focuses/shed light on the effects of X (X = S in P1 and X = O in P2) in C 11 H 7 NSX and R (R = H in P3, R = OCH 3 in P4, and R = Cl in P5) in C 18 H 9 ON 2 S 2 -R on structural features and band gaps of the polythiophenes containing benzo[ d ]thiazole and benzo[ d ]oxazole by the Density Function Theory (DFT) method/calculation. The structural features including the electronic structure lattice constant (a), shape, total energy (E tot ) per cell, and link length (r), are measured via band gap (E g ) prediction with the package of country density (PDOS) and total country density (DOS) of material studio software. The results obtained showed that the link angle and the link length between atoms were not changed significantly while the E tot was decreased from E tot = – 1904 eV (in P1) to E tot = – 2548 eV (in P2) when replacing O with S; and the E tot of P3 was decreased from E tot = – 3348 eV (in P3) when replacing OCH 3 , Cl on H of P3 corresponding to E tot = – 3575 eV (P4), – 4264 eV (P5). Similarly, when replacing O in P1 with – S to form P2, the E g of P1 was dropped from E g = 0.621 eV to E g = 0.239 eV for P2. The E g of P3, P4, and P5 is E g = 0.006 eV, 0.064 eV, and 0.0645 eV, respectively. When a benzo[ d ]thiazole was added in P1 (changing into P3), the E g was extremely strongly decreased, nearly 100 times (from E g = 0.621 eV to E g = 0.006 eV). The obtained results serve as a basis for future experimental work and used to fabricate smart electronic device.

In the title 1,4-di­hydro­pyridine derivative, the 1,4-di­hydro­pyridine ring makes an angle of 82.19 (13)° with the thio­phene ring. In the crystal, N—H⋯O and C—H⋯O hydrogen bonds as well as C—H⋯π inter­actions link the mol­ecules into a three-dimensional network.

The synthesis, spectroscopic data, crystal and molecular structures of two N′-(1-phenylbenzylidene)-2-(thiophen-3-yl)acetohydrazides, namely N′-[1-(4-hydroxyphenyl)benzylidene]-2-(thiophen-3-yl)acetohydrazide, C13H10N2O2S, (3a), and N′-[1-(4-methoxyphenyl)benzylidene]-2-(thiophen-3-yl)acetohydrazide, C14H14N2O2S, (3b), are described. Both compounds differ in the substituent at the para position of the phenyl ring: –OH for (3a) and –OCH3 for (3b). In (3a), the thiophene ring is disordered over two orientations with occupancies of 0.762 (3) and 0.238 (3). The configuration about the C=N bond is E. The thiophene and phenyl rings are inclined by 84.0 (3) and 87.0 (9)° for the major- and minor-occupancy disorder components in (3a), and by 85.89 (12)° in (3b). Although these dihedral angles are similar, the conformation of the linker between the two rings is different [the C—C—C—N torsion angle is −ac for (3a) and −sc for (3b), while the C6—C7—N9—N10 torsion angle is +ap for (3a) and −sp for (3b)]. A common feature in the crystal packing of (3a) and (3b) is the presence of N—H...O hydrogen bonds, resulting in the formation of chains of molecules running along the b-axis direction in the case of (3a), or inversion dimers for (3b). The most prominent contributions to the surface contacts are those in which H atoms are involved, as confirmed by an analysis of the Hirshfeld surface.