Directional Dynamic Covalent Motion of a Carbonyl Walker on a Polyamine Track.
Fiche publication
Date publication
mai 2015
Auteurs
Membres identifiés du Cancéropôle Est :
Pr LEHN Jean-Marie
Tous les auteurs :
Kovaricek P, Lehn JM
Lien Pubmed
Résumé
Controlled directional displacement of a molecular group has been achieved based on dynamic covalent motions implementing the reactional features of the imine bond. ortho-Carboxybenzaldehyde derivatives are able to form stable adducts with both primary and secondary amines as imines or as amino lactones, respectively, depending on the acidity of the medium. They may thus perform pH-driven intramolecular "walking" along a non-symmetric polyamine chain, in which an imine serves as the terminus under basic conditions on one end of the chain and a lactone formed on a secondary hydroxylamine nitrogen on the other end serves as the terminal site upon addition of acid. The displacement between the termini occurs stochastically through reversible change in valency at the carbon site of the carbonyl group between imine, aminal, iminium and amino lactone form. On the other hand, the directionality results from the stabilisation of the terminal products under given pH conditions. By its ability to undergo interconversion between CN and O-C-N moieties, the ortho-carboxybenzaldehyde group extends the realm of dynamic covalent chemistry of imines to secondary amines and opens new perspectives in this field.
Référence
Chemistry. 2015 May 26