Designed non-symmetrical 4,7-pi-extended-2,1,3-benzothiadiazole derivatives: Synthesis guided by DFT predictions

A series of rationally designed, non-symmetrical, 4,7-π-extended-2,1,3-benzothidiazole derivatives had their electronic and geometrical properties evaluated by means of DFT calculations. The data obtained from the calculated 2,1,3-benzothiadiazole (BTD) intermediates allowed the design and synthesis of a final structure bearing a fluorine-containing aromatic group on one side of the BTD ring and a C≡C spacer linking a long chain-containing (C8) aromatic group on the other side. This specific molecular architecture is expected to display liquid crystalline behavior. The new designed structure was therefore synthesized in good overall yield using cross-coupling reactions (Suzuki and Sonogashira reactions). Copyright © 2013 John Wiley & Sons, Ltd.