BARREIRA-FONTECHA, J. ... et al, 2011. Double template effect in [4+4] Schiff base macrocycle formation; an ESI-MS study. Dalton Transactions, 40(45), pp.12040-12043.
The mechanism of self-assembly of a polynuclear complex
of a [4 + 4] Schiff base iminomethylenediphenolate macrocycle
[BaCu4(4 + 4)]2+ via a non-macrocyclic dialdehyde intermediate
has been followed using ESI-MS of the reaction
solutions. Both assembly of the intermediate and Schiffbase
condensation with diamine give rise to single products;
formation of the intermediate metallacycle is fast but Schiffbase
condensation ismuch slower. Both intermediate complex
andmacrocyclic product have been structurally characterised.