3,3'-[o-Phenylenebis(methyleneoxy)]-bis(6-chloroflavone) and 3,3'-propylenedioxybis[6-chloro-2-(2-furyl)-4H-1-benzopyran-4-one]

The title compound 3,3'-[o-phenylenebis(methyleneoxy)]bis(6-chloroflavone), C(38)H(24)Cl(2)O(6), (I), crystallizes in the monoclinic space group C2/c, with the molecules lying across twofold rotation axes so that there is half a molecule in the asymmetric unit, while the other title compound, 3,3'-propylenedioxybis[6-chloro-2-(2-furyl)-4H-1-benzopyran-4-one], C(29)H(18)Cl(2)O(8), (II), crystallizes in monoclinic space group P2(1)/n with one molecule in the asymmetric unit. In both compounds, the benzopyran moiety is nearly planar, with dihedral angles between the two fused rings of 1.43 (8) degrees in (I), and 2.54 (7) and 3.00 (6) degrees with respect to the benzopyran moieties in the two halves of (II). The furan rings are twisted by 8.3 (1) and 8.4 (1) degrees in the two halves of (II). In both compounds, the molecular structure is stabilized by intramolecular C-H.O hydrogen bonds, while the crystal packing is stabilized by C-H.Cl and C-H.O intermolecular hydrogen bonds in (I) and (II), respectively.