organic compounds
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The title compound, C21H15FN2O2, features an approximately planar 1H-benzo[f]chromene fused-ring system (r.m.s. deviation for the 14 non-H atoms = 0.052 Å), with the fluorobenzene ring being almost perpendicular to this [dihedral angle = 85.30 (7) °]. The furan ring has a flattened half-chair conformation, with the methine C atom deviating by 0.132 (2) Å from the plane of the remaining atoms (r.m.s. deviation = 0.0107 Å). In the crystal, inversion dimers are formed via pairs of amine–cyano N—HN hydrogen bonds. The dimers are connected into a three-dimensional architecture by C—HN(cyano), C—Hπ and π–π [intercentroid distance = 3.6671 (10) Å] interactions.
organic compounds
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In the title compound, C21H15FN2O2, the furan ring has a flattened half-chair conformation [the methine C atom lies 0.136 (2) Å above the C5 plane which has an r.m.s. deviation of 0.0229 Å]. Overall, the 1H-benzo[f]chromene fused-ring system approximates a plane (r.m.s. deviation of the 14 non-H atoms = 0.049 Å). The fluorobenzene ring is almost perpendicular to this plane [dihedral angle = 89.58 (8)°]. Zigzag supramolecular tapes along the b axis are the most notable feature of the crystal packing. This arises through an alternating sequence of 12-membered {HNC3N}2 and eight-membered {HNCO}2 synthons. These are connected into a three-dimensional architecture by π–π [intercentroid distance for centrosymmetrically related fluorobenzene rings = 3.5181 (10) Å] and C—Hπ interactions.
organic compounds
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In the title compound, C21H15BrN2O2, the 14 non-H atoms of the 4H-benzo[h]chromene fused-ring system are approximately coplanar (r.m.s. deviation = 0.129 Å). Within this system, the 4H-pyran ring adopts a flattened half-chair conformation with the methine C atom lying 0.281 (4) Å above the plane of the remaining atoms (r.m.s. deviation = 0.0446 Å). The bromobenzene ring is almost perpendicular to the fused-ring system [dihedral angle = 85.34 (13)°]. In the crystal, supramolecular layers parallel to (101) are sustained by amine–cyano N—HN and amine–methoxy N—HO hydrogen bonds. The layers stack with interactions of the type (bromobenzene)C—Hπ(outer-C6 ring of the fused-ring system) connecting them.
organic compounds
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In the title compound, C24H20FN3O2, despite the 4H-pyran ring having a flattened half-chair conformation [the methine C atom lies 0.257 (3) Å above the plane of the remaining atoms with an r.m.s. deviation of 0.0295 Å], the 14 non-H atoms of the 4H-benzo[h]chromene residue are approximately coplanar (r.m.s. deviation = 0.081 Å). The benzene ring is nearly perpendicular to this plane [dihedral angle = 76.18 (10)°], but the planar (r.m.s. deviation = 0.033 Å) dimethylmethanimidamide substituent is coplanar [dihedral angle = 1.96 (12)°]. In the crystal, centrosymmetric dimeric aggregates arise from C—HN interactions, and these are connected into supramolecular layers in the ab plane by C—Hπ and π–π [intercentroid (central C6 ring)(outer C6 ring)i distance = 3.8564 (14) Å] interactions.
organic compounds
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The title compound, C10H5FN2, is a monoclinic (P21/c) polymorph of the previously reported triclinic (P-1) form [Antipin et al. (2003). J. Mol. Struct. 650, 1–20]. The 13 non-H atoms in the title polymorph are almost coplanar (r.m.s. deviation = 0.020 Å); a small twist between the fluorobenzene and dinitrile groups [C—C—C—C torsion angle = 175.49 (16)°] is evident in the triclinic polymorph. In the crystal, C—HN interactions lead to supramolecular layers parallel to (-101); these are connected by C—Fπ interactions.