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In the title compound, C20H19NO5, the dihedral angle between the mean plane of the pyran ring (which has a half-chair conformation) and the benzene ring of the chromeno ring system is 7.21 (7)°. The dihedral angle between the mean plane of the chromeno ring system and the isoxazole ring is 21.78 (6)°, while the isoxazole ring forms a dihedral angle of 72.60 (8)° with the attached phenyl ring. In the crystal, molecules are linked via pairs of C—H
O hydrogen bonds, forming inversion dimers with an R22(10) ring motif. These dimers are linked via C—HN hydrogen bonds, forming chains along [001].
O hydrogen bonds, forming inversion dimers with an R22(10) ring motif. These dimers are linked via C—HN hydrogen bonds, forming chains along [001].organic compoundsOpen access
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In the title compound, C18H14N2O2, the pyran ring of the chromeno ring system has a half-chair conformation, and the dihedral angle between its mean plane and the benzene ring is 5.3 (2)°. The isoxazole ring forms a dihedral angle of 74.6 (2)° with the attached benzene ring and is inclined to the mean plane of the chromeno ring system by 15.06 (19)°. In the crystal, there are no significant intermolecular interactions.
organic compoundsOpen access
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In the title compound, C17H11BrN2O2, the five-membered isoxazole ring has an envelope conformation with the C atom bearing the phenyl ring as the flap. The pyran ring has a half-chair conformation. In the chromeno ring system, the dihedral angle between the mean plane of the pyran ring and the benzene ring is 4.68 (2)°. The dihedral angle between the mean planes of the chromeno ring system and the isoxazole ring is 13.79 (15)°. The latter forms a dihedral angle of 34.10 (17)° with the phenyl ring. In the crystal, molecules are linked by C—HN hydrogen bonds, forming an undulating two-dimensional network parallel to the ab plane.
N hydrogen bonds, forming an undulating two-dimensional network parallel to the ab plane.organic compoundsOpen access
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The title compound, C19H17NO5, comprising two stereogenic C atoms of the same configuration, crystallizes in a centrosymmetric space group as a racemate. The pyran ring adopts a half-chair conformation, while the isoxazole ring adopts an envelope conformation with the C atom bonded to the methoxyphenyl group as the flap. The dihedral angle between the mean plane of the pyran ring and the adjacent benzene ring is 5.86 (5)°. In the crystal, molecules are linked by a weak C—HO hydrogen bond, forming a chain along the a axis.
O hydrogen bond, forming a chain along the a axis.organic compoundsOpen access
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The title compound, C17H11ClN2O2, which contains two stereogenic C atoms, crystallizes in a centrosymmetric space group as a racemate. The pyran ring and the isoxazole ring adopt sofa and twisted conformations, respectively. The dihedral angle between the benzene ring and the mean plane through the near coplanar atoms of the pyran ring is 4.17 (5)°. The molecular conformation features a weak C—HO contact. In the crystal, C—HO hydrogen bonds link the molecules, forming chains along the a-axis direction.
O contact. In the crystal, C—HO hydrogen bonds link the molecules, forming chains along the a-axis direction.organic compoundsOpen access
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In the title compound, C13H9ClN2O, the dihedral angle between the acrylonitrile C=C—CN plane and the quilonine ring system is 71.3 (2)°. In the crystal, molecules are linked by O—HN hydrogen bonds, forming chains along [01-1]. The chains are linked into a three-dimensional network through C—HN interactions.
N hydrogen bonds, forming chains along [01-1]. The chains are linked into a three-dimensional network through C—HN interactions.organic compoundsOpen access
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There are two independent molecules (A and B) in the asymmetric unit of the title compound, C14H12ClNO3. The mean planes of the methyl ester unit (Cmethyl—O—C=O; r.m.s. deviation = 0.051 Å for molecule A and 0.016 Å for molecule B) and the chloroquilonine ring system (r.m.s. deviation = 0.023 Å for molecule A and 0.014 Å for molecule B) form dihedral angles of 63.5 (1)° in molecule A and 78.1 (1)° in molecule B. The main difference between the two independent molecules is reflected in the (H)O—C—C=C(H2) torsion angle which is −109.7 (2)° in molecule A and 10.6 (2)° in molecule B. An intramolecular O—HO hydrogen bond is observed in molecule A. In the crystal, molecules A and B are linked into pairs via bifurcated O—H(N,Cl) hydrogen bonds and a weak C—HO hydrogen bond links pairs of molecules into chains along [100].
O hydrogen bond is observed in molecule A. In the crystal, molecules A and B are linked into pairs via bifurcated O—H(N,Cl) hydrogen bonds and a weak C—HO hydrogen bond links pairs of molecules into chains along [100].organic compoundsOpen access
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In the title compound, C25H21BrN2O2, the fused isoxazolidine ring adopts an envelope conformation with the N atom at the flap and the mean plane of the ring makes dihedral angles of 54.37 (12) and 87.32 (13)°, respectively, with the adjacent phenyl and benzene rings. The tetrahydropyran ring has a half-chair conformation. In the crystal, molecules are linked into a double-column structure along the b-axis direction through weak C—HO and C—Hπ interactions.
O and C—Hπ interactions.
