1-Methyl-3-p-tolyl-3,3a,4,9b-tetrahydro-1H-chromeno[4,3-c]isoxazole-3a-carbonitrile

In the title compound, C19H18N2O2, the dihedral angle between the mean planes of the fused chromeno and isoxazole units is 43.71 (7)°. The isoxazole and pyran rings exhibit envelope and half chair conformations, respectively. The crystal packing is stabilized by intermolecular C—H⋯π interactions.

In the title compound, C 19 H 18 N 2 O 2 , the dihedral angle between the mean planes of the fused chromeno and isoxazole units is 43.71 (7) . The isoxazole and pyran rings exhibit envelope and half chair conformations, respectively. The crystal packing is stabilized by intermolecular C-HÁ Á Á interactions.

1-Methyl
In the title molecule (Fig 1), the fused benzene and pyran rings forming the chromeno system are inclined to one another at a dihedral angle of 4.47 (7)° between the best planes of the rings. The six membered pyran ring adopts a half chair conformation with puckering amplitude Q= 0.4782 (15)Å, θ = 50.93 (17)° and φ = 278.3 (2)° (Cremer & Pople, 1975). In the pyran ring the C-C bond distances vary from a minimum of 1.3901 (19)Å to a maximum of 1.5332 (19)Å in comparison with a typical aromatic bond length of 1.384 (13)Å (Allen et al., 1987). This could be attributed to the presence of the heteroatom O1 in the cyclic system and also to the fusion of the pyran and isoxazole ring systems (Rybarczyk-Pirek et al., 2002).
The fusion between the isoxazole and the pyran rings at C7 and C8 is in cis-form. The dihedral angle between the fused chromeno and the isoxazole moieties is 43.71 (7)°.
The isoxazole ring adopts an envelope conformation at N1 with puckering parameters q2 = 0.5179 (14)Å and φ2 = 217.11 (16)° (Cremer & Pople,1975). In the isoxazole ring, enlargement of bond lengths and bond angles are observed at the points of linkages of substituents and fusion to the pyran ring (Raju et al., 2002).
The phenyl ring (C12-C17) substituent is almost perpendicular to the five membered isoxazole ring, the dihedral angle between them being 81.26 (8)°. The geometric parameters of the title compound agree well with reported structure (Gangadharan et al., 2011).
The crude product was diluted with water (10 ml), dilute HCl (5 ml) and extracted with ethylacetate (20 ml). The organic layer was washed with brine solution (10 ml) and concentrated. The crude product was purified by column chromatography to provide the pure desired product as colourless solid.
supplementary materials sup-2 Refinement All hydrogen atoms were placed in calculated positions with C-H = 0.93-0.98Å and refined in riding model with isotropic displacement parameters: U iso (H) = 1.5U eq (C) for methyl group and U iso (H)=1.2U eq (C) for other groups.