Imine Macrocycle with a Deep Cavity: Guest‐Selected Formation of syn/anti Configuration and Guest‐Controlled Reconfiguration

Abstract

A dynamic covalent bond is one of the ideal linkages for the construction of large and robust organic architectures. In the present article, we show how organic templates can efficiently transform a complex dynamic imine library into a dynamic imine macrocycle. Not only is the constitution well controlled, but also the syn/anti host configuration is efficiently selected and even the orientation of the guest in the asymmetric cavity of the host can be well aligned. This is attributed to the delicate balance and the cooperation of multiple noncovalent interactions between the hosts and the guests. Through sequential additions of three guests in appropriate amounts, controlled structural reconfiguration of dynamic covalent architectures has been achieved for the first time.

Oxatub[4]arene: a smart macrocyclic receptor with multiple interconvertible cavities

“…Recently, we employed dynamic combinatorial chemistry 18 and constructed a pair of dynamic configurational macrocycles which can interconvert. 19 The two configurations have different cavity parameters and different guests can thermodynamically select different host isomers. Research on similar but covalent receptors confirms the two isomers have very different guest preferences and binding abilities.…”

Directional Shuttling of a Stimuli‐Responsive Cone‐Like Macrocycle on a Single‐State Symmetric Dumbbell Axle

“…To realize the abovementioned molecular machines,w e needed as timuli-responsive three-dimensional macrocycle with ac one-like inner cavity.I ne arlier publications, [12] we reported several syn-configured naphthotubes [13] with aconelike cavity.T hese macrocycles can form complexes with av ariety of neutral molecules or organic cations.H owever, they are not stimuli-responsive.Herein, we synthesized apair of new naphthotubes each containing two secondary amines in their backbones.The syn-configured (1a,yield:7.5 %) and anti-configured naphthotubes (1b,y ield:2 6%)w ere produced together and can be separated through column chromatography.T heir structures were confirmed by 2D NMR spectroscopy (Supporting Information, Figures S1-S4) and X-ray single-crystal analysis ( Figure 2c). Syn-configured isomer 1a possesses ac one-like cavity and is responsive to acid-base chemistry (Supporting Information, Figures S5-S7).…”

Selective encapsulation of neutral molecules by endo-functionalized molecular tubes

“…[2] Recently, it has been demonstrated that naphthalene and the bisnaphthalene cleft are very good scaffolds for constructing molecular receptors. [3][4][5] On this basis, we reported molecular tubes with endo-functionalized urea and thiourea groups and carefully studied their molecular recognition behaviour to neutral molecules. [2,6] In this presentation our continued efforts to encapsulate neutral guests inside these endo-functionalized molecular tubes and the obtained crystallographic results are demonstrated.…”