Organic Crystals with Controlled Chirality and Space Group

摘要

Helices are one of the most fundamental and sophisticated structures with various fascinating functions,and thus they have attracted chemists.In the crystalline state,molecules tend to construct 2-fold (21) helical structures owing to factors such as cancelling of dipole moments and closed packing.Indeed,over 70％ of crystals registered in the Cambridge Structural Database (CSD) (Jan.1.2012) contain 21 helical axes.The fact leads us to come up with the novel idea that crystal design can be achieved by controlling bundling of the 21 helices as well as their chiral properties.However,there is a fundamental problem that their handedness of the 21 helices have not been distinguished yet on the basis of crystallographic studies because of their symmetry operation as 180° rotation and one-halftranslation.