Foldamer-based helicate displaying reversible switching between two distinct conformers

Abstract

A new double-stranded dinuclear helicate that displays conformational switching in response to temperature was prepared by self-assembly of an aromatic helical foldamer and dichloropalladium(ii). The relative populations of the two helicate conformers, syn-anti and syn-syn, were demonstrated to be reversibly modulated through temperature control.

Transformation networks of metal–organic cages controlled by chemical stimuli

“…In this review, we detail transformations between discrete architectures, where at least one of the species in the network is a three-dimensional metal–organic cage. Novel examples of transformations involving other types of self-assembled structures, 42 including helicates, 43,44 macrocycles, 45,46 other one- and two-dimensional assemblies, 47,48 and extended structures 49 such as metal–organic frameworks, 50 metallopolymers 51–53 and soft materials, 54 fall beyond the scope of this review. As others 41 and our group 40 have recently reviewed strategies to covalently modify coordination assemblies after their formation, we do not treat this type of chemical transformation herein.…”

Extended enantiopure ortho-phenylene ethylene (o-OPE)-based helical systems as scaffolds for supramolecular architectures: a study of chiroptical response and its connection to the CISS effect

“…Within this context, foldamers based on conjugated subunits constitute a privileged scaffold for a number of different reasons: i) they can be easily prepared by iterative protocols using simple conjugated monomers with different geometry, ii) the functionality present in such monomers can cooperatively act to strengthen their properties or even create new ones, and iii) they can also interact dynamically with the environment. In fact, many aromatic foldamers can be switched between different states by different stimuli such as the presence of light, [18][19][20][21][22] changes in temperature, [23][24][25][26] solvent composition, 27 anion, [28][29][30][31][32] cation, [33][34] or water [35][36][37][38] binding, and redox processes. 39,40 Moreover, foldamers are able to generate chirality in a dynamic way even using achiral monomers/repeating units.…”

Sequence-Controlled Stimuli-Responsive Single–Double Helix Conversion between 1:1 and 2:2 Chloride-Foldamer Complexes

“…Systems that utilize anion–receptor interactions have also emerged, for example, bicyclic guanidiniums, iodo-pyridinium ethynylenes, diammonium bis-pyridiniums, isophthalamides, oligo-ureas, oligo-pyrroles, , and aryl-triazole foldamers, which have all been stabilized with various anions. Solid-state forms of these double helices ,, are more common than those in solution. ,, Futhermore, despite the various examples of single helices that are responsive − and switchable, − examples of ion-bound foldamers displaying facile and reversible conversion between double and single helices are unknown, and this is true for both anion- and cation-stabilized helices.…”