N′-(2,6-Difluoro­benzyl­idene)pyridine-4-carbohydrazide

In the title compound, C13H9F2N3O, the pyridine ring forms a dihedral angle of 16.92 (7)° with the benzene ring. In the crystal, mol­ecules are linked via N—H⋯O, C—H⋯O and C—H⋯F, with the same O atom accepting two bonds

2-Bromo-1,3-bis­(4-chloro­phen­yl)prop-2-en-1-one

In the title compound, C15H9BrCl2O, the two benzene rings are twisted from each other with a dihedral angle of 47.33 (8)°. The crystal structure is stabilized by aromatic π–π inter­actions between the benzene rings of neighbouring mol­ecules [centroid–centroid distance = 3.680 (2) Å], and by weak inter­molecular C—H⋯O and C—H⋯Cl inter­actions. Additionally, the crystal structure exhibits a short intra­molecular C—H⋯Br contact (H⋯Br = 2.69 Å)

4-Methyl­benzoic acid–N′-[(E)-4-methyl­benzyl­idene]pyridine-4-carbohydrazide–water (1/1/1)

In the title hydrated 1:1 adduct, C8H8O2·C14H13N3O·H2O, the Schiff base mol­ecule exists in an E conformation with respect to the N=C bond [1.2843 (13) Å] and the dihedral angle between the pyridine ring and the benzene ring is 1.04 (5)°. In the crystal, mol­ecules are linked by N—H⋯O, C—H⋯O, O—H⋯O and O—H⋯N hydrogen bonds into sheets lying parallel to the ab plane. The crystal structure also features π–π inter­actions with centroid–centroid distances of 3.6224 (6) and 3.7121 (6) Å

Ethyl 4-(2,4-dichloro­phen­yl)-6-(6-meth­oxy-2-naphth­yl)-2-oxocyclo­hex-3-ene-1-carboxyl­ate

In the title compound, C26H22Cl2O4, the cyclo­hexenone ring adopts an approximate half-chair conformation, with two C atoms displaced by −0.485 (6) and 0.218 (6) Å from the plane of the other four ring atoms. The dihedral angles between its four almost coplanar [maximum deviation = 0.006 (2) Å] atoms and the benzene and naphthalene ring systems are 59.26 (13) and 79.94 (9)°, respectively. The dihedral angle between the aromatic rings systems is 77.14 (7)°. A short intra­molecular C—H⋯Cl contact generates an S(6) ring. In the crystal, mol­ecules are linked by C—H⋯O and C—H⋯Cl inter­actions to generate a three-dimensional network

(2E)-1-(2,4-Di­chloro­phen­yl)-3-(quinolin-8-yl)prop-2-en-1-one

The geometric parameters of the mol­ecule of the title compound, C18H11Cl2NO, a chalcone derivative, are in the usual ranges. The central C=C double bond is trans configured. The dihedral angle between the two aromatic residues is 41.90 (8)°

(2E)-1-(2,4-Di­chloro­phen­yl)-3-(2-hy­droxy­phen­yl)prop-2-en-1-one

The geometric parameters of the title mol­ecule, C15H10Cl2O2, are in the ususal ranges. The central double bond is trans configured. The dihedral angle between the dichloro­phenyl and hydroxy­phenyl rings is 71.38 (3)°. The crystal packing is stabilized by O—H⋯O hydrogen bonds and C—H⋯O contacts

(2E)-1-(2,4-Di­chloro­phen­yl)-3-(4-nitrophen­yl)prop-2-en-1-one

In the title compound, C15H9Cl2NO3, the central double bond is trans configured and the dihedral angle between the two planar fragments of the mol­ecule is 44.53 (4)°. The crystal packing is stabilized by C—H⋯O and C—H⋯Cl contacts

4,8-Dihydr­­oxy-2-methyl-1,2,3,4-tetra­hydro­isoquinolinium chloride mono­hydrate

Geometric parameters of the title compound, C10H14NO2+·­Cl−·H2O, are in the usual ranges. The tetra­hydro­pyridine ring adopts a half-chair conformation with the methyl group in an equatorial and the hydr­oxy group in an axial position. The crystal packing is stabilized by O—H⋯O, O—H⋯Cl and N—H⋯Cl hydrogen bonds. The absolute configurations of both chiral centres have been determined to be R

(2E)-1-(3-Bromo­phen­yl)-3-(6-meth­oxy-2-naphth­yl)prop-2-en-1-one

In the title compound, C20H15BrO2, the prop-2-en-1-one fragment is substanti­ally twisted [C—C—C—O = 23.0 (11)°]. The dihedral angle between the benzene and naphthalene rings is 44.28 (13)°. The only possible directional inter­actions in the crystal are weak C—H⋯π contacts, which generate (001) sheets