Acentric Extended Solids by Self Assembly of 4,4′-Bipyrazolyls

The inter-ring angle φ of 4,4′-bipyrazolyls, which can be controlled by varying the 3,3′- and 5,5′-substituents, determines their association into different three-dimensional arrays through interaction of their self-complementary hydrogen-bond donor and acceptor sites. Thus, for φ≈90°, a (10,3)-b net is formed (see picture, top), while for φ≈60°, the inherently chiral (10,3)-c net is obtained (see picture, bottom).