3-Amino-1-(3,4-dimethoxyphenyl)-9,10-dihydrophenanthrene-2,4-dicarbonitrile

In the title compound, C24H19N3O2, the partially saturated ring adopts a distorted half-chair conformation with the methylene-C atom closest to the aminobenzene ring lying 0.664 (3) Å out of the plane defined by the five remaining atoms (r.m.s. deviation = 0.1429 Å. The dihedral angle [32.01 (10)°] between the benzene rings on either side of this ring indicates a significant fold in this part of the molecule. The dimethoxy-substituted benzene ring is almost orthogonal to the benzene ring to which it is attached [dihedral angle = 72.03 (9)°]. The molecule has been observed previously as the major component of a 1:19 co-crystal with 2-amino-4-(3,4-dimethoxyphenyl)-5,6-dihydrobenzo[ha]quinoline-3-carbonitrile [Asiri et al. (2011). Acta Cryst. E67, o2873–o2873]. Supramolecular chains with base vector [201] are formed in the crystal structure via N—H⋯O hydrogen bonds between the amino H atoms of one molecule interacting with the methoxy O atoms of a neighbouring molecule. The chains are linked into a three-dimensional architecture by C—H⋯π interactions.

In the title compound, C 24 H 19 N 3 O 2 , the partially saturated ring adopts a distorted half-chair conformation with the methylene-C atom closest to the aminobenzene ring lying 0.664 (3) Å out of the plane defined by the five remaining atoms (r.m.s. deviation = 0.1429 Å . The dihedral angle [32.01 (10) ] between the benzene rings on either side of this ring indicates a significant fold in this part of the molecule. The dimethoxy-substituted benzene ring is almost orthogonal to the benzene ring to which it is attached [dihedral angle = 72.03 (9) ]. The molecule has been observed previously as the major component of a 1:19 co-crystal with 2-amino-4-(3,4dimethoxyphenyl)-5,6-dihydrobenzo[ha]quinoline-3-carbonitrile [Asiri et al. (2011). Acta Cryst. E67, o2873-o2873]. Supramolecular chains with base vector [201] are formed in the crystal structure via N-HÁ Á ÁO hydrogen bonds between the amino H atoms of one molecule interacting with the methoxy O atoms of a neighbouring molecule. The chains are linked into a three-dimensional architecture by C-HÁ Á Á interactions.
In (I), Fig. 1, the partially saturated ring adopts a distorted twisted half chair conformation with the C2 atom lying 0.664 (3) Å out of the plane defined by the five remaining atoms [r.m.s. deviation = 0.1429 Å; maximum deviations = 0.1733 (11) Å for the C9 atom and -0.2097 (14) Å for the C10 atom]. The dihedral angle between the benzene rings on either side of this ring = 32.01 (10)°, indicating a significant fold in this part of the molecule. The dimethoxy-substituted benzene ring is almost normal to the plane of the benzene ring to which it is attached, forming a dihedral angle of 72.03 (9)° The O1-and O2-methoxy substituents are each slightly twisted out of the plane of the benzene ring to which they are attached as seen in the values of the C23-O1-C19-C18 and C24-O2-C20-C21 torsion angles of -13.7 (3) and -5.0 (3)°, respectively; they lie to opposite sides of the plane through the benzene ting.
The most prominent feature in the crystal packing is the formation of N-H···O hydrogen bonds whereby the amino-H atoms are connected to the two methoxy-O atoms of a neighbouring molecule leading to a seven-membered {···HNH···OC 2 O} synthon linked into twisted supramolecular chains, Fig. 2 and Table 1; the base vector is along [2 0 1].

Refinement
Carbon-bound H-atoms were placed in calculated positions [C-H = 0.95 to 0.99 Å, U iso (H) = 1.2 to 1.5U eq (C)] and were included in the refinement in the riding model approximation. The N-H atoms were located in a difference Fourier map, and were refined with a distance restraint of N-H = 0.88±0.01 Å; their U iso values were refined. Owing to poor supplementary materials sup-2 Acta Cryst. (2012). E68, o1118-o1119 agreement, the (1 15 5) reflection was omitted from the final cycles of refinement.

Figure 1
The molecular structure of (I) showing the atom-labelling scheme and displacement ellipsoids at the 50% probability level.

Figure 2
The supramolecular chain in (I) sustained by N-H···O hydrogen bonds shown as blue dashed lines.