Crystal structures of 2-benzyl­amino-4-(4-bromo­phen­yl)-6,7,8,9-tetra­hydro-5H-cyclo­hepta­[b]pyridine-3-carbo­nitrile and 2-benzyl­amino-4-(4-chloro­phen­yl)-6,7,8,9-tetra­hydro-5H-cyclo­hepta[b]pyridine-3-carbo­nitrile

In the title compounds, C24H22BrN3, (I), and C24H22ClN3, (II), the 2-amino­pyridine ring is fused with a cyclo­heptane ring, which adopts a half-chair conformation. The planes of the phenyl and benzene rings are inclined to that of the central pyridine ring [r.m.s. deviations = 0.0083 (1) and 0.0093 (1) A for (I) and (II), respectively] by 62.47 (17) and 72.51 (14)°, respectively, in (I), and by 71.44 (9) and 54.90 (8)°, respectively, in (II). The planes of the aromatic rings are inclined to one another by 53.82 (17)° in (I) and by 58.04 (9)° in (II). In the crystals of both (I) and (II), pairs of N—H⋯Nnitrile hydrogen bonds link the mol­ecules, forming inversion dimers with R22(12) ring motifs. In (I), the resulting dimers are connected through C—H⋯Br hydrogen bonds, forming sheets parallel to (10-1), and π–π inter­actions [inter-centroid distance = 3.7821 (16) A] involving inversion-related pyridine rings, forming a three-dimensional network. In (II), the resulting dimers are connected through π–π inter­actions [inter-centroid distance = 3.771 (2) A] involving inversion-related pyridine rings, forming a two-dimensional network lying parallel to (001).