Synthesis and chiroptical properties of optically active methacrylic polymers bearing the (S)- and/or (R)-2-hydroxysuccinimide moiety linked to thetrans-azobenzene group in the side chain

Abstract

The synthesis of novel optically active monomers, namely (S)-(+)- and (R)-(-)-2 methacryloyloxy-N-(4-azobenzene) succinimide, is described. The monomers have been radically polymerized to afford the corresponding optically active homopolymers, characterized by the presence of an optically active rigid succinimide ring in the side chain linked to the trans-azoaromatic system through the imide nitrogen atom. A series of copolymers containing both the enantiomeric monomers in different molar amounts, have also been prepared in order to observe possible effects on the optical activity of the resulting deritatives. The chiroptical and conformational properties of the polymers in solution have been investigated by circular dichroism measurements and compared with those of low molecular weight model compounds, purposely synthesized, with the aim to verify the existence of cooperative interactions between chromophoric groups disposed along the macromolecular chain according to dissymmetric conformations.