Solvent assisted control of the solid-state colour and photo-polymerizablity of anthraquinone appended diacetylene

Design and self-assembly of organic molecules into a functional nanostructure has currently attracted immense attention. Diacetylenes are known to self-assemble to form polydiacetylenes when irradiated, which have been used in myriads of sensing and non-sensing applications. In this work, aminoanthraquinone was appended to the diacetylene based long-chain monomers to dictate the self-assembly of the small molecule. The synthesized compound AQ-DA exhibited color changes in the solid-state when treated with different solvents. H-bonding and p -p interactions are in operation which affects the molecules differently in different solvents. The effect of solvent on the compound also influenced its polymerization in thin films which provided additional insight into the self-assembling behavior of the compound.

Fig. (a) General scheme of polymerization of diacetylene monomers with UV light, (b) Solvent induced colour change in AQ-DA followed by selective polymerization in the yellow film.