title: 2,2,9-Trimethyl-2,3-dihydro-pyrano[2,3-a]carbazol-4-(11H)-one.
abstract: The title compound, C(18)H(17)NO(2), was prepared from 1-hydr-oxy-7-methyl-carbazole and 3,3-dimethyl-acrylic acid with trifluoro-acetic acid as the cyclization catalyst. The mol-ecules contain an essentially planar 6-methyl-indole unit. The second aromatic ring is significantly bent away from the plane of this unit, with maximum deviations of 0.171 (1) and 0.185 (1) Å for two of the C atoms. In the crystal structure, there are neither N-H⋯O hydrogen bonds nor π-π stacking between the aromatic sections of neighboring mol-ecules. There is only one weak C-H⋯O hydrogen bond and a number of weak C-H⋯π inter-actions.
authors.forename: Makuteswaran
authors.initials: M
authors.lastname: Sridharan
authors.forename: Karnam J Rajendra
authors.initials: KJ
authors.lastname: Prasad
authors.forename: Matthias
authors.initials: M
authors.lastname: Zeller