Methyl 6-eth­oxy-3-phenyl-3a,4-dihydro-3H-chromeno[4,3-c]isoxazole-3a-car­boxylate

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—H...N hydrogen bonds, forming chains along [001].

3-(2-Methyl­phen­yl)-3a,4-dihydro-3H-chromeno[4,3-c]isoxazole-3a-carbo­nitrile

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.

Diethyl [(2-chloro­anilino)(1,3-diphenyl-1H-pyrazol-4-yl)meth­yl]phospho­nate

In the title compound, C₂₆H₂₇ClN₃O₃P, the mean plane of the central pyrazole ring forms a dihedral angle of 71.37 (14)° with the chloro­phenyl ring. In the crystal, mol­ecules are linked by pairs of N—H...O hydrogen bonds, forming inversion dimers with R²₂(10) ring motifs. The 3-phenyl ring is disordered with four C atoms occupying two sets of sites with an occupancy ratio of 0.748 (4):0.252 (4).

8-Bromo-3-phenyl-3a,4-dihydro-3H-chromeno[4,3-c]isoxazole-3a-carbo­nitrile

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—H...N hydrogen bonds, forming an undulating two-dimensional network parallel to the ab plane.