Shapeshifting molecules: the story so far and the shape of things to come

Abstract

This review describes the synthesis and application of shapeshifting molecules, whose covalent skeletons dynamically reconfigure in response to their surroundings.

Shape‐Shifting Molecules: Unveiling the Valence Tautomerism Phenomena in Bare Barbaralones

“…So far, NMR spectroscopy has been employed for the analysis of shapeshifting mixtures, but it is an arduous task to conclusively identify the individual structures rather than derive averaged chemical properties. However, as shown, the isolation conditions granted by the supersonic expansion enabled the study of each structure separately, instead of trying to deconvolute the dynamic equilibria in the condensed phase, [11,30] which may be perturbed due to interactions with…”

“…So far, NMR spectroscopy has been employed for the analysis of shape‐shifting mixtures, but it is an arduous task to conclusively identify the individual structures rather than derive averaged chemical properties. However, as shown, the isolation conditions granted by the supersonic expansion enabled the study of each structure separately, instead of trying to deconvolute the dynamic equilibria in the condensed phase, [11, 30] which may be perturbed due to interactions with the environment. We are fiercely exploring the full scope and capabilities of rotational spectroscopy coupled to a laser‐ablation vaporization source as a reliable characterization technique to unravel dynamic molecular systems.…”

Cover Picture: Shape‐Shifting Molecules: Unveiling the Valence Tautomerism Phenomena in Bare Barbaralones (Angew. Chem. Int. Ed. 18/2022)

“…So far, NMR spectroscopy has been employed for the analysis of shapeshifting mixtures, but it is an arduous task to conclusively identify the individual structures rather than derive averaged chemic al properties. How ever, as show n, the isolation conditions granted by the supersonic expansion enabled the study of each structure separately, instead of trying to deconvolute the dynamic equilibr ia in the condensed phase [11,30], w hich may be perturbed due to interactions w ith the environment. We are fiercely exploring the full scope and capabilities of rotational spectroscopy coupled to a laser-ablation vaporization source as a reliable characterization technique to unravel dynamic molecular systems.…”

Connecting Molecular and Supramolecular Shapeshifting by the Ostwald’s Nucleation Stages of a Star Giant Molecule

“…For example, in bulk self-assembly, the spherical molecules promote the formation of the plastic crystalline mesophases that have a long-range positional order but a short-range orientational order, whereas the cylindrical and discotic molecules facilitate the formation of the smectic and columnar liquid crystalline mesophases that have a longrange orientational order but a short-range positional order. 7,10−12 Although shapeshifting molecules have been developed to release the restrictions on the well-defined shapes of molecules and have thus been utilized in the adaptive chemistry, 13,14 the studies emphasized how the molecular shapeshifting alters the host−guest complexes in the solution phase. Besides, complexing the geometrical feature by synthesizing molecular shape amphiphiles, which possess building blocks of distinct shapes, also did not diversify the self-assembly pathway of synthetic molecules as each shape amphiphile still self-assembled into a specific supramolecular scaffold preferred by one of the constituent building blocks.…”