Crystal structure of 2-chloro-3-(di-meth-oxy-meth-yl)-6-meth-oxy-quinoline

The title compound, C13H14ClNO3, crystallizes with Z' = 2 in the space group Pca21, but a search for possible additional crystallographic symmetry found none. However, the crystal structure exhibits pseudosymmetry as the two independent mol-ecules are related by an approximate but non-crystallographic inversion located close to (0.38, 0.26, 1/2) in the selected asymmetric unit, and the structure exhibits partial inversion twinning. The approximate inversion relationship between the two mol-ecules in the selected asymmetric unit is clearly shown by comparison of the relevant torsion angle in the two mol-ecules; the corresponding torsion angles have similar, although not identical magnitudes but with opposite signs. The mean planes of the quinoline rings in the two independent mol-ecules are almost parallel, with a dihedral angle of only 0.16 (3)° between them, and the mutual orientation of these rings permits significant π-π stacking inter-actions between them [centroid-centroid distances = 3.7579 (15) and 3.7923 (15) Å]. In addition, the bimolecular aggregates which are related by translation along [010] are linked by a further π-π stacking inter-action [centroid-centroid distance = 3.7898 (15) Å], so forming a π-stacked chain running parallel to [010]. However, there are no C-H⋯N hydrogen bonds in the structure nor, despite the number of independent aromatic rings, are there any C-H⋯π hydrogen bonds; hence there are no direction-specific inter-actions between adjacent π-stacked chains.