Here we report an efficient synthesis of optically active ladder-type molecules and polymers through intramolecular cyclization of chiral triptycenes containing bis[2-(4-alkoxyphenyl)ethynyl]phenylene units. The electrophile-induced cyclization reactions are directed away from the bridgehead carbon atoms of triptycene by steric factors, thereby producing one-handed twisted ladder units without any detectable byproducts. Moreover, the quantitative and regioselective nature of this intramolecular cyclization allowed us to synthesize optically active ladder polymers with a welldefined one-handed helical geometry in which homoconjugated dibenzo[a,h]anthracene units are helically arranged along the main chain. This synthesis route enables the construction of a variety of nanoscale helical ladder architectures and provides an entry into new chiroptical materials.

We report the first direct chirality sensing of a series of chiral hydrocarbons and isotopically chiral compounds (deuterated isotopomers), which are almost impossible to detect by conventional optical spectroscopic methods, by a stereoregular polyacetylene bearing 2,2'-biphenol-derived pendants. The polyacetylene showed a circular dichroism due to a preferred-handed helix formation in response to the hardly detectable hidden chirality of saturated tertiary or chiroptical quaternary hydrocarbons, and deuterated isotopomers. In sharp contrast to the previously reported sensory systems, the chirality detection by the polyacetylene relies on an excess one-handed helix formation induced by the chiral hydrocarbons and deuterated isotopomers via significant amplification of the chirality followed by its static memory, through which chiral information on the minute and hidden chirality can be stored as an excess of a single-handed helix memory for a long time.

We report the synthesis of one-dimensional supramolecular polymers composed of one-handed helical macromolecules bearing fluorescent pendant groups and the generation of circularly polarized light on the basis of hierarchical chiral amplification starting from a tiny amount of chiral substituent. Copolymerization of benzo­[1,2-b:4,5-b′]­dithiophene-appended achiral/chiral isocyanides (99:1, mol/mol) with a solid-state photoluminescence feature afforded submicrometer supramolecular fibers, in which almost perfect single-handed helical polyisocyanides were noncovalently connected end to end. The resulting helical supramolecular polymers were further helically assembled to form a cholesteric liquid crystal film with an intense circularly polarized luminescence (CPL) signal. Surprisingly, the supramolecular system containing only 0.01 mol % of the chiral monomer unit also emitted the observable circularly polarized light owing to multiple chiral amplification from an infinitesimal point chirality to helical chirality and then to supramolecular chirality. Furthermore, chiral information was efficiently transferred from the helically assembled supramolecular system containing 1 mol % of the chiral unit to achiral dye molecules blended in the film, allowing full-color tunable induced CPL with luminescence dissymmetry factors greater than 1.0 × 10–2. This unprecedentedly strong chiral amplification enables the creation of helical supramolecular polymers and chirally assembled systems with various chiral functions based solely on an infinitesimal chiral source.

A series of chiral fluorescent polymers containing optically active triptycene units in the main chain were synthesized via Sonogashira–Hagihara coupling copolymerizations of (R,R)- or (S,S)-2,6-diethynyltriptycene with a range of diiodoaryls. Their optical and chiroptical properties were investigated under various solution conditions. We observe that these polymers emitted circularly polarized light owing to the chiral triptycene framework with a handed twisted rigid structure, and the fluorescence colors could be tuned in the whole visible range from blue to red by replacing the achiral comonomer units. They possessed luminescence dissymmetry factors of approximately 1.0 × 10–3, regardless of the incorporated comonomer units.

Living systems achieve sophisticated functions using supramolecular protein assemblies, in which the protein building blocks possess a specific secondary structure and are noncovalently arranged in a preprogrammed manner. Herein, we demonstrate the one-step synthesis of one-dimensional macromolecular assemblies by simply mixing a glycine-based isocyanide with a nickel catalyst, in which helical constituent polymers are linked end-to-end through multiple hydrogen bonds. The applicable scope of this approach is not confined to a particular monomer bearing a specially designed pendant, but covers a wide range of glycine-based isocyanides with or without aromatic and other functional groups. Surprisingly, copolymerization with an analogous chiral isocyanide (1 mol %) afforded an almost perfect one-handed helical supramolecular fiber owing to intramolecular/intermolecular dual chiral amplifications. The simplicity and broad applicability of this approach, which can also afford exquisite chiral amplification, enable the creation of a wide variety of functional supramolecular assemblies and provide access to new supramolecular materials.