A novel approach to the classical Sergeants and Soldiers effect, using chiral Sergeants and chiral Soldiers, allows control over both helical and external chirality in helical polymers. In the systems reported here, it is possible to induce the same helical sense ( M or P) from either of the two enantiomers of a chiral pendant group ["chiral Soldier", major component; i.e., ( R)- or ( S)-1] when it faces a single enantiomer of an appropriate "chiral Sergeant" [minor component; i.e., ( S)-2]. For instance, the copolymer series poly[( R)-1 - co-( S)-2], poly[( S)-1 - co-( S)-2], and poly[( rac)-1 - co-( S)-2] adopt the same P helix even though the major component shows the opposite absolute configuration. This chiral-to-chiral communication effect is transmitted by the stabilization of different conformations in each enantiomeric form of the Soldier. As a result, this groundbreaking approximation to the Sergeants and Soldiers effect allows the preparation of a single-handed helix-which depends only on the Sergeant's configuration-with different chiralities on the helix periphery. Thus, a P helix can be decorated with the R isomer, S isomer, or even a racemic mixture of the chiral Soldier. A change in the absolute configuration of the Sergeant affords the opposite M helix, which can also be decorated with the R isomer, S isomer, or racemic mixture of the chiral Soldier.

para-positions with the two enantiomers of either -hydroxy-phenylacetic acid (1) and -chloro--phenylacetic acid (S-2) linked through an anilide bond. These monomers were further polymerized, and their secondary structure and dynamic behavior analyzed. Compiling information from these studies, and the structural data for other PPAs found in literature, we can state that anilide linkages in p-substituted polymers tend to generate compressed cis-cisoidal polyene structures, which can be transformed into more elongated cis-transoidal ones by external stimuli, while benzamide linkages in p-substituted polymers form mainly cis-transoidal scaffolds. The macromolecular structure of PPAs is also largely affected by the aromatic substitution pattern, adopting more stretched scaffolds once the pendant group is placed in meta or ortho positions, due to the steric hindrance generated by placing this group closer to the backbone.

Different communication mechanisms can be switched within a copolymer by acting on the conformational composition of the components and their chirality. Thus, a sergeant and soldiers effect is produced in two diastereomeric copolymer series, poly[(S)‐1r‐co‐(S)‐2(1−r)] and poly[(R)‐1r‐co‐(S)‐2(1−r)], owing to the presence in chloroform of a preferred conformation in (S)‐2, and a conformational equilibrium in 1, where a P helix is induced independently of the absolute configuration of the soldier. In THF, the presence of a conformational equilibrium at the pendants of the two components produces a reciprocal chiral enhancement effect by copolymerization of the two monomers, while in DMF, a third chiral to chiral communication switch is produced due to the presence of a single conformer at the pendant group of the two components. In such a case, a chiral conflict or chiral accord effect is produced depending if the two components induce the same or the opposite helical sense.