trans-1,2-Bis(8-hydroxy-2-quinolinyl)ethene: Comparison with trans-Stilbene

The title compound, (E)-1,2-ethylenediylbis(2-quinolin-8-ol), C₂₀H₁₄N₂O₂, was isolated chromatographically from the Wittig reaction of 8-hydroxy-2-quinolinecarbaldehyde, triphenyl(2-methylene-8-hydroxyquinolinyl)phosphonium chloride and n-butyllithium. The structure is almost planar with C₂ symmetry in the crystal. The olefinic C=C distance is 1.319 (3)Å and the structure consists of crystallographically equivalent molecules stacked along the b direction. These molecules are linked via zigzag hydrogen bonding between the quinolinol O atom of one molecule and the hydroxy H atom of another molecule. Such systematic hydrogen bonding on both sites of the molecule characterizes a novel backbone network.

-1