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Chiral information transmission in helical polymers bearing multi-chiral pen-dant groups is usually determined by the absolute configuration of the first chi-ral center. The second chiral residue usually has low-to-null influence in themacromolecular handedness of the polymer, due to its remote position respectto the polyene main chain. Here, we demonstrate how the stimuli responsiveproperties of diastereomeric polymers, obtained by changing the absolute con-figuration of the second chiral center, are different due to the unlike propertiesof diastereoisomers

The helix is one of the topological structures and it is inherently chiral; therefore, a large number of artificial helical polymers with controlled helicity have been synthesized, not only to mimic biological helices, but also to develop chiral materials with functionally. More specifically, poly(phenylacetylene)s (PPA)s are a family of dynamic helical polymers where the screw sense and/or elongation of the backbone can be modified by the action of different external stimuli such as pH, temperature or polarity of the solvent. However, dynamic helical polymers bearing multi-chiral pendants in which the power of the chiral center located at a remote position remains unexplored. This thesis is focused on the development of new synthetic chiral materials based on poly(phenylacetylene)s (PPA)s bearing multi-chiral pendant groups. Their structure, dynamic behavior, chiral information transmission mechanisms and stimuli-responsive properties were studied, leading to promising new materials for the future rational design of novel smart materials with specific properties.

In helical polymers, helical sense induction is usually commanded by teleinduction mechanism, where the largest substituent of the chiral residue directly attached to the main chain is the one that commands the helical sense. In this work, different helical structures with different helical senses are induced in a helical polymer [poly-(phenylacetylene)] when the conformational composition of two different dihedral angles of a pendant group with more than two chiral residues is tamed. Thus, while the dihedral angle at chiral residue 1 [(R)- or (S)-alanine], attached to the backbone, produces an extended or bent conformation in the pendant resulting in two scaffolds with different stretching degree, the second dihedral angle at chiral residue 2 [(R)- or (S)-methoxyphenylacetamide] places the substituents of this chiral center in a different spatial orientation, originating opposite helical senses at the polymer that are induced through a total control of the “chiral overpass effect”