4-Di­phenyl­phosphanyl-8-methyl-1,5-naphthyridine

In the title compound, C₂₁H₁₇N₂P, the dihedral angles between the 1,5-naphthyridine ring system (r.m.s. deviation = 0.005 Å) and the phenyl rings are 89.18 (8) and 77.39 (8)°. The phenyl rings are almost perpendicular, making a dihedral angle of 88.12 (8)°. The only possible inter­molecular inter­action is a very weak aromatic π–π stacking inter­action [centroid–centroid separation = 3.898 (2) Å].

1,4-Di­bromo-2,5-di-p-toluoyl­benzene

In the title compound, C₂₂H₁₆Br₂O₂, which has approximate non-crystallographic inversion symmetry, the dihedral angles between the central ring and the pendant rings are 89.1 (4) and 82.4 (3)°; the dihedral angle between the pendant rings is 12.1 (4)°. In the crystal, the packing is influenced by van der Waals forces and no aromatic π–π stacking is observed.