Supramolecular liquid crystals containing isoquinoline hydrogen-bonded acceptors

Abstract

6-Dodecyloxyisoquinoline IS (1) has been synthesized and utilized as a proton acceptor to generate a series of novel mesogenic supramolecules. Two mesogenic supramolecular dimers IS-OBA and IS-COOBA have been constructed from a 1:1 molar ratio of IS complexed either with 4-decyloxybenzoic acid OBA (2) or with 4-decyloxycarbonylbenzoic acid COOBA (3). A kinked mesogenic supramolecular trimer, i.e. a double H-bonded complex (IS)-THDA, has been constructed from a 2:1 molar ratio of IS complexed with 2,5-thiophenedicarboxylic acid THDA (4). The mesogenic properties of the H-bonded complex (IS2)-THDA are compared with those of previously reported H-bonded complexes (C12PS)-THDA and (C12PP2)-THDA consisting of a 2:1 molar ratio of trans -4-dodecyloxy-4-stilbazole C12PS 2 (5) or 4-dodecyloxypyridine C12PP2 (6) with THDA. Significantly, the first isoquinoline-based supramolecular liquid crystals have been built, and their mesogenic properties have been introduced or modified by fused- N -heterocyclic rings.