The title indan-1-one derivative, C(16)H(11)BrO, is planar, the r.m.s. deviation for all 18 non-H atoms being 0.071 Å. The configuration about the C=C bond [1.337 (5) Å] is E. In the crystal, supra-molecular layers in the ab plane are formed by C-H⋯O inter-actions, involving the bifurcated carbonyl O atom, as well as C-H⋯π inter-actions. The studied crystal was an inversion twin.

The title indan-1-one derivative, C(18)H(14)O, is planar with an r.m.s. deviation for all 19 non-H atoms of 0.098 Å. The conformation about each of the C=C bonds [1.343 (3) and 1.349 (3) Å] is E. Supra-molecular layers in the bc plane, mediated by C-H⋯O and π-π [ring centroid-centroid distance = 3.5282 (15) Å] inter-actions, feature in the crystal packing.

In the title compound, C(28)H(20)F(3)NO(3), the pyrrolidine ring adopts a half-chair conformation. The other five-membered rings adopt envelope conformations with the spiro and methylene C atoms as the flap atoms. In the crystal, mol-ecules are connected via weak C-H⋯O hydrogen bonds, forming sheets parallel to the bc plane.

In the title compound, C(27)H(20)BrNO(3), two intra-molecular C-H⋯O hydrogen bonds both form S(6) rings. The pyrrolidine ring adopts a twisted conformation about the C-C bond bearing the indane ring systems. The other two five-membered rings within the indane systems are in shallow envelope conformations, with the spiro C atoms as the flap atoms. The mean plane of the pyrrolidine ring [maximum ...

In the title compound, C(27)H(20)BrNO(3), the pyrrolidine ring adopts a half-chair conformation, while the other five-membered rings adopt flattened envelope conformations with the spiro C atoms as the flap atoms. An intra-molecular C-H⋯O hydrogen bond occurs, generating an S(6) ring. In the crystal, mol-ecules are connected via weak C-H⋯O hydrogen bonds, forming chains along the c axis.