Dynamic Covalent Self‐Assembly Based on Oxime Condensation

다국어 초록 (Multilingual Abstract)

Oxime, whose dynamic nature was reported to be switchable between ON/OFF by tuning the acidity, is employed in a novel type of dynamic covalent approach that is amenable to use in water for self‐assembly of purely organic molecules with complex topology. In strongly acidic conditions, the dynamic nature of oxime is turned ON, allowing occurrence of error‐checking and therefore a catenane and a macrocycle self‐assembled in high yields. In neutral conditions, oxime ceases to be dynamic, which helps to trap the self‐assembled products even when the driving forces of their formation are removed. We envision that this switchable behaviour might help, at least partially, to resolve a commonly encountered drawback of dynamic covalent chemistry, namely that the intrinsic stability of the self‐assembled products containing dynamic bonds, such as imine or hydrazone, are often jeopardized by their reversible nature.
In stark saurer wässriger Lösung ist die Oximbindung dynamisch, sodass sich sowohl ein Catenan als auch ein Makrocyclus selbstorganisiert in relativ hohen Ausbeuten bilden können. Unter neutralen Bedingungen kommt diese Dynamik fast vollständig zum Erliegen, und das selbstorganisierte Catenan ist im Feststoff wie in Lösung kinetisch inert – auch bei Temperaturerhöhung, Chromatographie oder Austausch des Gegenions.