Optically active 2,4-dimethylglutarate azoaromatic esters of known relative configuration as models of dyads present in the related methacrylic polymeric derivatives

Novel chiral dimeric models of isotactic (meso) and syndiotactic (dl) dyads of optically active methacrylic polymers containing in the side-chain the pyrrolidinyl group of one single configuration linked through the nitrogen atom to the azobenzene chromophore, have been synthesized by functionalization of 2,4-dimethylglutaric acids with known streoisomeric composition.Their characterization afforded the possibility to investigate the relationship between the chiroptical and spectroscopic properties displayed by the dimeric model compounds and those of the related homopolymeric derivatives with known main chain stereoregularity.In particular, the optical rotation values and circular dichroism spectra of the models allow to establish the contribution of main chain microtacticity to the overall optical activity of the polymeric derivative.