Triple Self‐Sorting in Constitutional Dynamic Networks: Parallel Generation of Imine‐Based Cu^I, Fe^II, and Zn^II Complexes

Abstract

Three imine‐based metal complexes, having no overlap in terms of their compositions, have been simultaneously generated from the self‐sorting of a constitutional dynamic library (CDL) containing three amines, three aldehydes, and three metal salts. The hierarchical ordering of the stability of the three metal complexes assembled and the leveraging of the antagonistic and agonistic relationships existing between the constituents within the constitutional dynamic network corresponding to the CDL were pivotal in achieving the sorting. Examination of the process by NMR spectroscopy showed that the self‐sorting of the FeII and ZnII complexes depended on an interplay between the thermodynamic driving forces and a kinetic trap involved in their assembly. These results also exemplify the concept of “simplexity”—the fact that the output of a self‐assembling system may be simplified by increasing its initial compositional complexity—as the two complexes could self‐sort only in the presence of the third pair of organic components, those of the CuI complex.

Behavior of Constitutional Dynamic Networks: Competition, Selection, Self‐sorting in Cryptate Systems

“…Again, the second example shows that the greater complexity of a system may lead to a simpler output, further illustrating simplexity [10a–c,11,12] . Although the observed effect is quite small in comparison to the first case, due to the high selectivity of each cryptand for its respective metal cation, it is clear that the same features apply to the higher‐order, [3×3] 3D CDNs.…”

“…This example demonstrates several points: i) in the case where, in the reduced networks both receptors “prefer” binding different substrates , the combination of such reduced networks into a full network increases the amount of “preferred” cation bound by each corresponding receptor: it is a result of synergy by dynamic competition in a network, where the combined action of both receptors (as each selectively sequesters its “preferred” cation and, thus, leaves the other cation more available for the other receptor); ii) if however, in the reduced networks, both receptors preferentially bind the same substrate , the overall outcome of the full network will be dominated by the highest binding constant ; iii) in both cases, the output of a more complex system is simpler than the sum of outputs of simpler systems composing it, thus defining the notion of “simplexity” [10a–c,11,12] …”

“…Thus, moving from a reduced , [1×2] three‐component to a full , [2×2] four‐component and more complex system, may yield an output that is simpler than the sum of the outputs of both reduced networks. It amounts to a synergistic evolution (co‐evolution) [12b] towards a state of “simplexity” , corresponding to a self‐sorting process [10a–c,11,12] …”

“…In earlier works, we have revealed the occurrence of such effects in DCvC [11] as well as in DNCC [10a–c,12] . Thus, metallosupramolecular dynamic libraries consisting of mixtures of reversible imine ligands and metal cations generated initially complex libraries of many constituents which were markedly reduced after all components had been introduced (for instance from nine to three constituents) [12a] in processes that also presented hierarchical relations.…”

“…An increasing number of self‐sorting chemical systems have been reported in the literature in the past years [9,10] as a result of more and more careful encoding of steric, electronic, and geometric information into molecular components and their communication between hierarchical levels of selection, the presence of all the components in a mixture being necessary to produce a “simpler” output [10b] …”