1,3-Diphenyl-3,4-dihydro-benzo[b][1,6]naphthyridine

Abstract

The title compound, C(24)H(18)N(2), is the first structural example containing the 3,4-dihydro-benzo[b][1,6]naphthyridine fragment. It was synthesized from 2,4,6,8-tetra-phenyl-3,7-diaza-bicyclo-[3.3.1]nonan-9-one and was crystallized from a methanol-ethanol solution over two years as a racemate. The C=N double bond [1.2868 (15) Å] is bent significantly out of the plane of the aromatic bicyclic ring system [N-C-C-C = -157.63 (12)°] and out of the plane of the phenyl ring bonded at the 1-position [N-C-C-C = 41.15 (16)°].

Fig. 1.

ORTEP plot (Johnson, 1965) showing the atomic numbering scheme. The probability ellipsoids are drawn at the 50% probability level, the H atoms are drawn with arbitrary radii. Selected distances: C1—N2 1.2868 (15) Å, C1—C101 1.4862 (16) Å, C1—C11 1.4936 (16) Å, N2—C3 1.4769 (14) Å, C3—C21 1.5128 (15) Å, C3—C4 1.5369 (15) Å, C4—C41 1.5073 (15) Å, C41—N5 1.3152 (14) Å, C41—C101 1.4293 (15) Å, N5—C51 1.3764 (14) Å.