Crystal structure and Hirshfeld surface analysis of methyl 4-[(E)-2-(5-bromo-2-meth-oxy-benzyl-idene)hydrazin-yl]-3-nitro-benzoate.

The title compound, C16H14BrN3O5, is a novel halogen (Br) substituted hydrazine derivative. The hydrazine derivatives were the group of compounds with the general structure, R1R2C=NNH2 (Uppal et al., 2011 ▸), with the central RC=NNH2 moiety bridging two different groups on both sides. An all-trans configuration of the backbone (RC=NNH2) results in an extended mol-ecular conformation. The dihedral angle between the 5-bromo-2-meth-oxy-phenyl ring and the nitrophenyl ring is 4.4 (3)°. Intra-molecular N-H⋯O inter-actions form S(6) graph-set motifs, while C-H⋯O and C-H⋯N inter-actions form S(5) graph-set motifs. Symmetry-related mol-ecules are linked by C-H⋯O inter-molecular inter-actions forming an R21(10) graph-set motif. There are nearly face-to-face directional specific π-π stacking inter-actions between the centroids of the nitrophenyl ring and the benzene ring of the 5-bromo-2-meth-oxy group [centroid-centroid distance = 3.6121 (5) Šand slippage = 1.115 Å], which also contributes to the mol-ecular packing. The Hirshfeld surface analysis was performed in order to visualize, explore and qu-antify the inter-molecular inter-actions in the crystal lattice of the title compound.

2-(4-Methyl-phen-yl)-7-(2-methyl-prop-oxy)-4H-chromen-4-one-6-chloro-2-(4-methyl-phen-yl)-7-(2-methyl-prop-oxy)-4H-chromen-4-one (19/1).

The title co-crystal, 0.95C(20)H(20)O(3)·0.05C(20)H(19)ClO(3), arises as the chloride carried over during the synthesis shares a position with an aromatic H atom; the partial occupancies are 0.947 (2) and 0.053 (2) for H and Cl, respectively. The mol-ecular structure is stabilized by intra-molecular C-H⋯O contacts, forming pseudo five- and six-membered rings with S(5) and S(6) graph-set motifs, respectively. The crystal structure features π-π stacking inter-actions between the centroids of the central fused ring systems [centroid-centroid distance = 3.501 (2) Å].

(2E)-1-[2-Hydr-oxy-4-(2-methyl-prop-oxy)phen-yl]-3-(4-methyl-phen-yl)prop-2-en-1-one.

The benzene rings in the title compound, C(20)H(22)O(3), form a dihedral angle of 10.39 (8)°. Overall, the mol-ecule is approximately planar with the exception of one of the terminal methyl groups; excluding this group, the r.m.s. deviation for the remaining 22 non-H atoms is 0.0968 Å. The conformation about the C=C bond is E, and an intra-molecular O-H⋯O hydrogen bond leads to the formation of an S(6) motif. In the crystal, linear supra-molecular chains are formed along the a axis via C-H⋯O contacts, and these are connected into double chains via C-H⋯π inter-actions.