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Updated: Sep 26, 2026

Synthesis of Information-bearing Peptoids and their Sequence-directed Dynamic Covalent Self-assembly
Published on: February 6, 2020
A guest-induced assembly of a molecular box from methylcobaloxime and 1, 4-phenylenebisboronic acid
Renata Dreos1, Giorgio Nardin, Lucio Randaccio
1Dipartimento di Scienze Chimiche, Università di Trieste, via Licio Giorgieri 1, 34127, Trieste, Italy. dreos@univ.trieste.it
Abstract:
The guest-induced synthesis of a molecular box from methylaquacobaloxime and 1,4-phenylenebisboronic acid, with pyrazine (pz) as guest, is described. The resulting supramolecular species was characterized by X-ray structural analysis, 1H and 13C NMR spectroscopy, and low-resolution electrospray ionization (ES) mass spectrometry. The assembly was monitored by a time dependent 1H NMR experiment, which showed that the guest thermodynamically drives the assembly of the host. The effectiveness of pyrazine in this role arises from its having both the correct geometry and a sufficiently low pKa value. Several other ditopic ligands were tested, but none led to formation of an analogous product. However, a second supramolecular species was formed in the case of ethylenediamine (en). X-ray structural analysis and 1H and 13C spectroscopy revealed that this is closely related to the first, with a phenyl side removed and the pz bridge substituted by the en bridge.
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