Crystal structure of 2-chloro-3-(dimethoxymethyl)-6-methoxyquinoline

Abstract

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 molecules 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 molecules in the selected asymmetric unit is clearly shown by comparison of the relevant torsion angle in the two molecules; 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 molecules 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 interactions 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 interaction [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 interactions between adjacent π-stacked chains.