A Self-Sorting Scheme Based on Tetra-Urea Calix[4]arenes


  • We are grateful for funding from the Deutsche Forschungsgemeinschaft (Bo 523/14 and SFBs 625/765) and the Fonds der Chemischen Industrie (FCI). C.A.S. thanks the FCI for a Dozentenstipendium.


Size and shape do matter: When dimerized in nonpolar solvents, an equimolar mixture of eleven tetra-urea calix[4]arenes with different wide-rim substituents self-sorts into only six out of 35 different homo- and heterodimers (see picture). Since the calixarene scaffold and the four urea units are the same in all cases, the self-sorting process is driven only by the cooperative action of steric requirements and stoichiometry.

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