3-[(E)-2-(2-Meth-oxy-phen-yl)vin-yl]-5,5-di-methyl-cyclo-hex-2-enone.

The title compound, C17H20O2, has an E conformation about the bridging C=C bond. The cyclo-hexene ring adopts an envelope conformation with the dimethyl-substituted C atom as the flap. Its mean plane makes a dihedral angle of 7.

3-[(E)-2-(4-Chloro-phen-yl)ethen-yl]-5,5-di-methyl-cyclo-hex-2-en-1-one.

In the title compound, C16H17ClO, the cyclo-hexene ring adopts a half-chair conformation and the best plane through the six ring atoms makes a dihedral angle of 6.69 (7)° with the chlorophenyl ring. In the crystal, pairs of C-H⋯O hydrogen bonds link the mol-ecules into centrosymmetric R 2 (2)(20) dimers.

3-(4-Chloro-phen-yl)-1-cyclo-propyl-2-(2-fluoro-phen-yl)-5-phenyl-pentane-1,5-dione.

In the title compound, C26H22ClFO2, the cyclo-propane ring is disordered over two orientations, with site-occupancy factors of 0.64 (2) and 0.36 (2).

(E)-3-[4-(Di-fluoro-meth-oxy)-3-hy-droxy-phen-yl]-1-phenyl-prop-2-en-1-one.

In the title compound, C16H12F2O3, the plane of the phenyl ring makes a dihedral angle of 3.22 (8)° with that of the benzene ring. The mol-ecule has an E conformation about the C=C bond.

5-(4-Chloro-phen-yl)-1-cyclo-propyl-2-(2-fluoro-phen-yl)-3-phenyl-pentane-1,5-dione.

In the title compound, C(26)H(22)ClFO(2), the cyclo-propane ring makes dihedral angles of 45.7 (2), 49.0 (2) and 65.

1-Cyclo-propyl-2-(2-fluoro-phen-yl)-5-(4-fluoro-phen-yl)-3-phenyl-pentane-1,5-dione.

In the title compound, C(26)H(22)F(2)O(2), the cyclo-propane ring makes dihedral angles of 47.6 (2), 51.3 (2) and 63.