4-(Oct­yloxy)phenyl 2-oxo-2H-chromene-3-carboxyl­ate

In the title compound, C₂₄H₂₆O₅, the 2H-chromene ring system is essentially planar, with a maximum deviation of 0.029 (2) Å from the best-fit mean plane incorporating both rings. The dihedral angle between the 2H-chromene ring system and the benzene ring is 21.00 (1)°. In the crystal, pairs of C—H...O hydrogen bonds generate an R₂²(8) ring pattern. These contacts are bolstered by weaker bifurcated C—H...O hydrogen bonds.

4′-Cyano­biphenyl-4-yl 7-diethyl­amino-2-oxo-2H-chromene-3-carboxyl­ate

In the title compound, C₂₇H₂₂N₂O₄, the dihedral angles between the central benzene ring and the cyano­benzene ring and the 2H-coumarin ring system (r.m.s. deviation = 0.014 Å) are 22.95 (11) and 75.59 (8)°, respectively. Both terminal C atoms of the pendant diethyl­amino group lie to the same side of the coumarin ring system [deviations = 1.366 (2) and 1.266 (2) Å]. In the crystal, mol­ecules are linked by C—H...O and C—H...N hydrogen bonds and a C—H...π inter­action, generating a three-dimensional network.

4-(Dec­yloxy)phenyl 2-oxo-7-trifluoro­methyl-2H-chromene-3-carboxyl­ate

The title compound, C₂₇H₂₉F₃O₅, is a liquid crystal (LC) and exhibits enanti­otropic SmA phase transitions. In the crystal, the dihedral angle between the 2H-chromene ring system and the benzene ring is 62.97 (2)°. The three F atoms of the –CF₃ group are disordered over two sets of sites with occupancy factors 0.71 (4):0.29 (4). In the crystal, pairs of C—H...O hydrogen bonds form inversion dimers and generate R₂²(10) rings. The structure also features C—H...F and C—H...π inter­actions along [100] and [010], respectively.