organic compounds
Open access
In the title compound, C16H15BrN2O4, the six-membered carbocyclic ring of the chromene moiety adopts an envelope conformation with the disordered methylene C atom as the flap. The pyran ring is almost orthogonal to the chlorophenyl ring, making a dihedral angle of 87.11 (12)°. The amine-group N atom deviates significantly from the pyran ring [0.238 (3) Å]. The molecular structure is stabilized by an intramolecular N—HO hydrogen bond, which generates an S(6) ring motif. In the crystal, molecules are linked via C—HO hydrogen bonds, which generate C(8) chains running parallel to the b axis. The chains are linked by C—Hπ interactions. The methylene-group C atom of the chromene system that is disordered, along with its attached H atoms and the H atoms on the two adjacent C atoms, has an occupancy ratio of 0.791 (7):0.209 (7).
organic compounds
Open access
The title compound, C16H15ClN2O4, contains a chiral centre and crystallizes as a racemate. The methylene group β-positioned to the carbonyl group is partially (21%) disordered. It flips to the opposite sides of the corresponding six-membered carbocycle by −0.304 (3) and 0.197 (11) Å, producing alternative envelope conformations. The planes of the pyran and chlorophenyl rings form a dihedral angle of 86.25 (9)°. The molecular structure is characterized by an intramolecular N—HO interaction, which generates an S(6) ring motif. The corresponding amino N atom deviates from the plane of the pyran ring by 0.1634 (19) Å. In the crystal, molecules are linked via C—HO hydrogen bonds, forming C(8) chains running parallel to the b-axis direction. The crystal structure also features C—Hπ interactions.
organic compounds
Open access
The title compound, C16H15N3O6, is asymmetric with a chiral centre located in the pyran ring and crystallizes as a racemate. The six-membered carbocyclic ring adopts an envelope conformation with the central CH2 C atom as the flap. The amine N atom deviates from the mean plane of the pyran ring by 0.1365 (15) Å. The nitrophenyl ring is almost orthogonal to the pyran ring and the mean plane of the six-membered carbocyclic ring, the dihedral angle between their mean planes being 88.30 (7) and 87.61 (8)°, respectively. The molecular structure is stabilized by an intramolecular N—HO hydrogen bond, which generates an S(6) ring motif. In the crystal, molecules are linked via C—HO hydrogen bonds, forming infinite bands lying parallel to (-110) and composed of alternate R22(24) and R24(12) graph-set ring motifs. The crystal structure is further stabilized by C—Hπ interactions, forming a three-dimensional structure.