Helix-helix interactions – homochirality and heterochirality

Abstract

The relatively simple molecule 2-amino-4-(thiazolin-2-yl)phenol, 1, as its acetonitrile solvate crystallises such that the lattice can be considered to contain heterochiral sheets of helical, N⋯HO H-bonded polymers which are linked within their sheets by weaker N⋯HN H-bonds between adjacent helices of opposite chirality. Weaker interactions of the CH⋯π type can be discerned as linking helices of the same chirality between these sheets, these interactions being reinforced by weaker interactions still involving the acetonitrile solvent molecules. A similar analysis can be conducted of the helical structures found within the lattice of the related compound 4-(methoxycarbonyl)-2-aminophenol, 2, although here it is more difficult to define the hierarchy of the weak interactions observed.