Complementarity of 2,6-Dimethanolpyridine and Di(ethylene glycol) in the Complexation of Na+Ions: Attaching Multiple Copies of [2]Catenane Branches to Isophthalaldehyde-Containing Cores
Journal
Journal of Organic Chemistry
Journal Volume
86
Journal Issue
19
Pages
13491-13502
Date Issued
2021
Author(s)
Abstract
In this study we found that 2,6-dimethanolpyridine displays good complementarity toward di(ethylene glycol) for the complexation of Na+ ions, allowing us to use this recognition system for the efficient synthesis of hetero[2]catenanes; indeed, it allowed us to attach multiple copies of [2]catenanes to branched systems presenting multiple isophthalaldehyde units. When we attempted to form a catenane from a preformed macrocycle featuring only a single di(ethylene glycol) unit, reacting it with a di(ethylene glycol) derivative presenting two amino termini, isophthalaldehyde, and templating Na+ ions [i.e., with the aim of using di(ethylene glycol)·Na+·di(ethylene glycol) recognition to template the formation of the interlocked imino macrocycle], the yields of the hetero[2]catenane and homo[2]catenane, comprising two imino macrocyclic units, were both poor (14% and 7%, respectively). In contrast, when one or two 2,6-dimethanolpyridine units were present in the preformed macrocycles, their reactions with the same diamine, dialdehyde, and Na+ ions provided the hetero[2]catenanes with high selectivity and efficiency (44% and 64% yields, respectively), with minimal formation of the competing homo[2]catenane. The high complementary of the 2,6-dimethanolpyridine·Na+·di(ethylene glycol) ligand pair allowed us to synthesize [2]catenane dimers and trimers directly from corresponding isophthalaldehyde-presenting cores, with yields, after subsequent reduction and methylation, of 42% and 31%, respectively. ? 2021 American Chemical Society.
Subjects
Alkylation
Amines
Dimers
Ethylene
Ethylene glycol
Ions
Branched system
Catenanes
Efficient synthesis
Glycol derivatives
Glycol units
Isophthalaldehydes
Macrocycles
Na+ ions
Recognition systems
[2]catenanes
Polyols
Type
journal article