1,2-Bis[(1,3-benzodioxol-5-yl)methyl­idene]hydrazine

The complete mol­ecule of the title compound, C₁₆H₁₂N₂O₄, is generated by the application of a centre of inversion. The (1,3-benzodioxol-5-yl)methyl­idene fused-ring system is approximately planar (r.m.s. deviation = 0.020 Å) and is essentially coplanar with the central hydrazine group [dihedral angle = 5.08 (9)°]. Weak π–π inter­molecular inter­actions are observed [centroid–centroid distance = 3.8553 (8) Å], providing some packing stability.

(1E,4E)-1-(3-Nitro­phen­yl)-5-phenyl­penta-1,4-dien-3-one

In the title compound, C₁₇H₁₃NO₃, the dihedral angle between the benzene rings is 31.21 (5)°. In the crystal, inversion dimers linked by pairs of C—H...O hydrogen bonds occur. A C—H...π inter­action is also indicated.

(2E)-2-[(3E)-4-Phenyl­but-3-en-2-yl­idene]hydrazinecarboxamide

In the title compound, C₁₁H₁₃N₃O, the phenyl ring is disordered over two sites, with occupancy factors in a 0.520 (17):0.480 (17) ratio. The dihedral angle between the ring planes of the major and minor components of the disordered ring is 12.9 (2)°. In the crystal, mol­ecules are linked by N—H...O hydrogen bonds, forming R₂²(8) ring motifs. C—H...O, C—H...N and C—H...π inter­actions also occur.

1,2-Bis(3-phen­oxy­benzyl­idene)hydrazine

Mol­ecules of the title compound, C₂₆H₂₀N₂O₂, reside on crystallographic centres of inversion located at the mid-point of the N—N bond. The benzyl­idene ring is essentially coplanar with the central hydrazine group, with an inter­planar angle of 4.5 (2)°, whereas the phenyl ring is oriented at 34.0 (3)° with respect to the mean plane of the central 1,2-dibenzyl­idenehydrazine group. In the crystal, C—H...π(arene)-ring inter­actions link mol­ecules about inversion centres.

1-(4,4′′-Difluoro-5′-meth­oxy-1,1′:3′,1′′-terphenyl-4′-yl)ethanone

In the title compound, C₂₁H₁₆F₂O₂, the central benzene ring is inclined at dihedral angles of 30.91 (8) and 46.88 (7)° to the two terminal fluoro-substituted rings. The dihedral angle between the two terminal fluoro-subsituted rings is 68.34 (8)°. An intra­molecular C—H...O hydrogen bond generates an S(6) ring motif. The crystal structure is stabilized by weak C—H...π inter­actions.

Ethyl 4,4′′-difluoro-5′-meth­oxy-1,1′:3′,1′′-terphenyl-4′-carboxyl­ate

In the title compound, C₂₂H₁₈F₂O₃, the two fluoro-substituted rings form dihedral angles of 25.89 (15) and 55.00 (12)° with the central benzene ring. The eth­oxy group in the mol­ecule is disordered over two positions with a site-occupancy ratio of 0.662 (7):0.338 (7). In the crystal, mol­ecules are linked by C—H...O hydrogen bonds into chains along the a axis. The crystal packing is further stabilized by C—H...π and π—π inter­actions, with centroid–centroid distances of 3.8605 (15) Å.

N-(4,6-Dimeth­oxy­pyrimidin-2-yl)-2-(3-methyl­phen­yl)acetamide

In the title compound, C₁₅H₁₇N₃O₃, the dihedral angle between the pyrimidine and benzene rings is 87.0 (7)°. In the crystal, mol­ecules are linked into inversion dimers with R₂²(8) graph-set motifs by a pair of N—H...O hydrogen bonds. Weak C—H...O hydrogen bonds and inter­molecular π–π inter­actions [centroid–centroid distance = 3.544 (1) Å] are also observed.