Hydrogen-bond networks in the binary complexes of trigonal molecules with 4,4′-bipyridine

Abstract

A 1 : 1 binary salt and a cocrystal of two chemically different trigonal symmetric donor molecules, 2,4,6-trimethyl-1,3,5-benzenetricarboxylic acid (MTAH₃) and 2,4,6-tris(4-hydroxyphenoxy)-1,3,5-triazine (HPT) with 4,4′-bipyridine (bipy) have been synthesized and the crystal structures have been studied. The MTAH₃·bipy salt shows an unprecedented parallel interpenetrated 3D bookshelf type of structure aided by C(8) type O–H⋯O and acid⋯pyridine O–H⋯N interactions. The HPT·bipy complex has a 2D → 3D parallel polycatenated pcu net aided by the usual hydroxy⋯pyridine synthon and supported by a C–H⋯O interaction. Both the complexes exhibit the formation of 3D structures from trigonal donors, contrary to the fact that trigonal species generally are being considered to be candidates for construction of 2D networks.