Date Published: May 01, 2010
Publisher: International Union of Crystallography
Author(s): Werner Seebacher, Robert Weis, Robert Saf, Ferdinand Belaj.
The title compound, C24H18N2, is the first structural example containing the 3,4-dihydrobenzo[b][1,6]naphthyridine fragment. It was synthesized from 2,4,6,8-tetraphenyl-3,7-diazabicyclo[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)°].
For the synthesis of 1,3-diphenyl-1,2,3,4-tetrahydrobenzo[b][1,6]naphthyridine, see: Sivakumar (2000 ▶). For the synthesis of 2,4,6,8-tetraphenyl-3,7-diazabicyclo[3.3.1]nonan-9-one, see Ravindran et al. (1991 ▶). For the crystal structures of other naphthyridine derivatives, see: Sivakumar et al. (2003 ▶); Laavanya et al. (2001 ▶).