Crystal structures of methyl (E)-3-(2-chloro-phen-yl)-2-({2-[(E)-2-nitro-vin-yl]phen-oxy}meth-yl)acrylate and methyl (E)-2-({4-chloro-2-[(E)-2-nitro-vin-yl]phen-oxy}meth-yl)-3-(2-chloro-phen-yl)acrylate

摘要

The title compounds, C19H16ClNO5, (I), and C19H15Cl2NO5, (II), both crystallize in the monoclinic space group P21. They differ essentially in the orientation of the methyl acetate group, with the C=O bond directed towards the NO2 group in (I) but away from it in (II). In compound (I), the mean plane of the methyl acrylate unit is planar, with a maximum deviation of 0.0044?(2)?? for the methyl C atom, while in (II) this deviation is 0.0147??. The inter-planar angles between the two aromatic rings are 74.87?(9) and 75.65?(2)° for compounds (I) and (II), respectively. In both compounds, the methyl acrylate and nitro-vinyl groups each adopt an E conformation about the C=C bond. In the crystal of (I), mol-ecules are linked by C—H?O hydrogen bonds forming chains along the b axis. The chains are linked via C—H?Cl hydrogen bonds, forming sheets parallel to the ab plane. The sheets are linked via C—H?π inter-actions, forming a three-dimensional structure. In the crystal of (II), mol-ecules are linked by pairs of C—H?O hydrogen bonds, forming inversion dimers with an R22(30) ring motif. The dimers are linked via C—H?O hydrogen bonds, forming sheets parallel to the ac plane and enclosing R44(28) ring motifs. The sheets are linked via parallel slipped π–π inter-actions (inter-centroid distances are both ca 3.86??), forming a three-dimensional structure.