RESUMEN
In the title compound, C17H15NO4, the conformation about the C=C double bond [1.348â (2)â Å] is E with the ketone group almost co-planar [C-C-C-C torsion angle = 7.2â (2)°] but the phenyl group twisted away [C-C-C-C = 160.93â (17)°]. The terminal aromatic rings are almost perpendicular to each other [dihedral angle = 81.61â (9)°] giving the mol-ecule an overall U-shape. The crystal packing feature benzene-C-Hâ¯O(ketone) contacts that lead to supra-molecular helical chains along the b axis. These are connected by π-π inter-actions between benzene and phenyl rings [inter-centroid distance = 3.6648â (14)â Å], resulting in the formation of a supra-molecular layer in the bc plane.
RESUMEN
In the title compound, C17H14N2O6, the conformation about the C=C double bond [1.345â (2)â Å] is E, with the ketone moiety almost coplanar [C-C-C-C torsion angle = 9.5â (2)°] along with the phenyl ring [C-C-C-C = 5.9â (2)°]. The aromatic rings are almost perpendicular to each other [dihedral angle = 86.66â (7)°]. The 4-nitro moiety is approximately coplanar with the benzene ring to which it is attached [O-N-C-C = 4.2â (2)°], whereas the one in the ortho position is twisted [O-N-C-C = 138.28â (13)°]. The mol-ecules associate via C-Hâ¯O inter-actions, involving both O atoms from the 2-nitro group, to form a helical supra-molecular chain along [010]. Nitro-nitro Nâ¯O inter-actions [2.8461â (19)â Å] connect the chains into layers that stack along [001].
RESUMEN
In the title compound, C16H20O6, the conformation about the C=C double bond [1.344â (2)â Å] is Z. With respect to this bond, the ketone is almost coplanar [C-C-C-O torsion angle = -179.60â (10)°] and the ester is almost perpendicular [C-C-C-O = 78.42â (13)°]. The meth-oxy substituents of the central benzene ring are either almost coplanar [C-C-O-C = 3.54â (15) and 177.70â (9)°] or perpendicular [C-C-O-C = 80.08 12)° for the central substituent]. In the crystal, the three-dimensional architecture features C-Hâ¯O and π-π [inter-centroid distance = 3.6283â (6)â Å] inter-actions.
RESUMEN
In the title compound, C(14)H(13)ClO(5), the five-membered ring is in an envelope conformation with the methyl-ene C-atom being the flap. The conformation about the C=C double bond [1.341â (2)â Å] is E. The chloro-propan-2-one residue is approximately orthogonal to the remaining mol-ecule [dihedral angle = 88.03â (6)°]. In the crystal, the mol-ecules associate via C-Hâ¯O inter-actions, involving both carbonyl-O atoms, giving rise to an undulating two-dimensional array in the ac plane.
RESUMEN
Two independent mol-ecules (A and B) comprise the asymmetric unit of the title compound, C21H18O4. There are significant conformational differences between the mol-ecules relating in particular to the relative orientation of the 3-oxo-2-(phenyl-methyl-idene)but-oxy substituent with respect to the superimposable chromen-2-one residues. To a first approximation, the substituents are mirror images; both are approximately perpendicular to the chromen-2-one fused ring system with dihedral angles of 88.50â (7) (A) and 81.96â (7)° (B). Another difference between the independent mol-ecules is noted in the dihedral angles between the adjacent phenyl and but-3-en-2-one groups of 8.72â (12) (A) and 27.70â (10)° (B). The conformation about the ethene bond in both mol-ecules is E. The crystal packing features C-Hâ¯O, C-Hâ¯π(ar-yl) and π-π [Cgâ¯Cg = 3.6657â (8) and 3.7778â (8)â Å] stacking inter-actions, which generate a three-dimensional network.