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Updated: May 24, 2026

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Ipso-Nitration of calix[6]azacryptands: intriguing effect of the small rim capping pattern on the large rim
Manuel Lejeune1, Jean-François Picron, Alice Mattiuzzi
1Laboratoire de Chimie Organique, Université Libre de Bruxelles (U.L.B.), avenue F. D. Roosevelt, 50 CP160/06, B-1050 Bruxelles, Belgium.
Abstract:
The ipso-nitration of calix[6]arene-based molecular receptors is a important synthetic pathway for the elaboration of more sophisticated systems. This reaction has been studied for a variety of capped calixarenes, and a general trend for the regioselective nitration of three aromatic units out of six in moderate to high yield has been observed. This selectivity is, in part, attributed to the electronic connection between the protonated cap at the small rim and the reactive sites at the large rim. In addition, this work highlights the fact that subtle conformational properties can drastically influence the outcome of this reaction.
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