Molecular baskets with amino acids at their rim1 are soluble in water and capable of trapping simulants of nerve agents, ammonium-based or other compounds, in their non-polar inner space. Photo-induced decarboxylation of basket 1 (Figure 1) reduces the solubility of this host in water, which subsequently precipitates together with the nerve agent simulant occupying its cavity.2 The process is simple, facile and effective and could amount to a novel method for removing minute quantities of targeted substances from aqueous environments. The results are of interest for advancing the areas of environmental chemistry, drug purification and/or sequestration of toxic compounds in biological systems. Furthermore, the irradiation of basket 2 containing three glutamic acids at its rim causes the exclusive removal of a-carboxylic groups while g-carboxylates remain intact. The chemical change triggers the aggregation and assembly of now amphiphilic 3 into vesicles.3 While basket 2 traps bis-ammonium guests to give stable ternary complexes (Kd &lt; mM) thereby removing them from bulk solvent, the photoinduced decarboxylation causes the release of these guests back to the solvent as aggregated 3 has lower affinity for guests (Kd &gt; mM). The concept is currently explored for directing the outcome of competing chemical reactions in water. In conclusion, the development of new photo switchable hosts is currently of interest for bottom-up preparation of programmable molecular devices capable of completing a series of chemical operations in complex environments.

Photo-responsive molecular baskets capable of removing/releasing targeted molecules in water

256th National Meeting (2018)

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