Crystal structure and Hirshfeld surface analysis of 2-amino-4-(4-methoxyphenyl)-6-oxo-1-phenyl-1,4,5,6-tetrahydropyridine-3-carbonitrile

In the crystal, strong C—H⋯O and N—H⋯N hydrogen bonds form dimers with (14) and (12) ring motifs between adjacent mol­ecules along the c-axis direction. Inter­molecular N—H⋯O and C—H⋯O hydrogen bonds connect these dimers to form a three-dimensional network. In addition, C—H⋯π inter­actions and π–π stacking inter­actions help to stabilize the packing.

The central tetra­hydro­pyridine ring of the title compound, C₁₉H₁₇N₃O₂, adopts a screw-boat conformation. In the crystal, strong C—H⋯O and N—H⋯N hydrogen bonds form dimers with R²₂(14) and R²₂(12) ring motifs, respectively, between consecutive mol­ecules along the c-axis direction. Inter­molecular N—H⋯O and C—H⋯O hydrogen bonds connect these dimers, forming a three-dimensional network. C—H⋯π inter­actions and π–π stacking inter­actions contribute to the stabilization of the mol­ecular packing. A Hirshfeld surface analysis indicates that the contributions from the most prevalent inter­actions are H⋯H (47.1%), C⋯H/H⋯C (20.9%), O⋯H/H⋯O (15.3%) and N⋯H/H⋯N (11.4%).

Crystal structure and Hirshfeld surface analysis of 5-acetyl-2-amino-4-(4-bromophenyl)-6-oxo-1-phenyl-1,4,5,6-tetrahydropyridine-3-carbonitrile

In the crystal, N—H⋯O hydrogen bonds link the mol­ecules into dimers with an (16) ring motif. Further N—H⋯O and N—H⋯N hydrogen bonds connect the dimers into chains along the c-axis direction. C—Br⋯π and C=O⋯π inter­actions stabilize the mol­ecular packing, resulting in a three-dimensional network.

The crystal structure of the title compound, C₂₀H₁₆BrN₃O₂, was determined using an inversion twin. Its asymmetric unit comprises two crystallographically independent mol­ecules (A and B) being the stereoisomers. Both mol­ecules are linked by pairs of N—H⋯O hydrogen bonds, forming a dimer with an R²₂(16) ring motif. The dimers are connected by further N—H⋯O and N—H⋯N hydrogen bonds, forming chains along the c-axis direction·C—Br⋯π inter­actions between these chains contribute to the stabilization of the mol­ecular packing. Hirshfeld surface analysis showed that the most important contributions to the crystal packing are from H⋯H, C⋯H/H⋯C, O⋯H/H⋯O, Br⋯H/H⋯Br and N⋯H/H⋯N inter­actions.

Crystal structure and Hirshfeld surface analysis of ethyl 6'-amino-2'-(chloro-meth-yl)-5'-cyano-2-oxo-1,2-di-hydro-spiro-[indoline-3,4'-pyran]-3'-carboxyl-ate

The mol-ecular conformation of the title compound, C17H14ClN3O4, is stabilized by an intra-molecular C-H⋯O contact, forming an S(6) ring motif. In the crystal, the mol-ecules are connected by N-H⋯O hydrogen-bond pairs along the b-axis direction as dimers with R 2 2(8) and R 2 2(14) ring motifs and as ribbons formed by inter-molecular C-H⋯N hydrogen bonds. There are weak van der Waals inter-actions between the ribbons. The most important contributions to the surface contacts are from H⋯H (34.9%), O⋯H/H⋯O (19.2%), C⋯H/H⋯C (11.9%), Cl⋯H/H⋯Cl (10.7%) and N⋯H/H⋯N (10.4%) inter-actions, as concluded from a Hirshfeld surface analysis.

Crystal Structure and Hirshfeld Surface Analysis of Acetoacetanilide Based Reaction Products

We report an unprecedented multicomponent reaction of acetoacetanilide with malononitrile leading to a structurally novel bicyclic product (9) in a high yield. The structure has been confirmed by X-ray crystallography and comparative Hirshfeld surface analysis of 5-cyano-2-hydroxy-2-methyl-N-phenyl-4-(yridine-4-yl)-6-(thiophen-2-yl)-3,4-dihydro-2H-pyran-3-carboxamide 2, 5-cyano-2-hydroxy-2-methyl-6-oxo-N-phenyl-4-(thiophen-2-yl)piperidine-3-carboxamide 4 and 2-(8-amino-7,8a-dicyano-1-imino-4a-methyl-3-oxo-2-phenyl-1,3,4,4a,5,8a-hexahydroisoquinolin-6(2H)-ylidene)-N-phenylacetamide 9.