Poly(isocyanide)s, Poly(quinoxaline‐2,3‐diyl)s, and Related Helical Polymers Used as Chiral Polymer Catalysts in Asymmetric Synthesis

Fulvenyl-Functionalized Polyisocyanides: Cross-Conjugated Electrochromic Polymers with Variable Optical and Electrochemical Properties

“…However, analyses of polymer batches with different molecular weights showed no correlation between the degree of polymerization and the absorption spectra of the polymers, even for low-MW batches with DP n < 10 (see Figures S2, S4, and S7). Conjugation along the polymer backbone therefore does not seem to substantially contribute to the overall absorption, likely because steric crowding of the PIC backbone leads to helical torsion angles between adjacent imine-groups (>35°). − Notably, PICs can also adopt a syndio -conformation wherein imine dyads assume a coplanar geometry (R–NC–CN–R: ≈180°), while being rotated by ca. 90° relative to neighboring imine groups.…”

“…In this paper, we report the first examples of compounds that formally represent polyfulvenes linked via the exocyclic fulvene double bond. To achieve this goal, we aimed at combining the electronic properties of fulvenes with those polyisocyanides − (PIC, Figure C,D).…”

“…PICs have been investigated extensively since the 1970s − but have attracted renewed interest with the recent development of new polymerization catalysts that allow the living polymerization of isocyanides. − This has opened an access to the preparation of a variety of block copolymers including PICs as coblocks to conjugated polymers. − Still, reports of PICs as electronic materials are comparatively rare and focus on the introduction of functional side chains, rather on taking advantage of the electronic properties of the polymer backbone. The backbone of PICs consists of consecutive sp 2 -hybridized imine-carbon atoms.…”