Controlling the Chair Conformation of a Mannopyranose in a Large‐Amplitude [2]Rotaxane Molecular Machine

Abstract

Molecular machines boarding now! Molecular machines containing dibenzo[24]crown-8 (DB24C8) and based on an anilinium and a pyridinium amide station have been prepared. The DB24C8 shuttles upon variation of pH and interacts differently with the pyridinium amide station depending on its substitution. When the DB24C8 sits around the disubstituted amide, the conformation of the pyranose changes from (1)C(4) to (4)C(1).

Effect of hydrogen-interactions on electrochemical behavior of bithiophene self-assembled monolayers containing amide moieties

“…It starts with the formation of the bithiophene azide 3, in 79% yield, through a nucleophilic substitution involving 1-azido-6-bromohexane [14]. 3 is then reduced using a common H 2 -Pd/C procedure, at atmospheric pressure, giving the corresponding amine 4 in close to quantitative yield.…”

Rotaxanes and pseudorotaxanes with threads containing pyridinium units

“…87 Their thread bears two stations: an anilinium and a monoor disubstituted pyridinium amide, and the ring is DB24C8 (Scheme 13). …”

Recent Advances in the Synthesis of Ammonium-Based Rotaxanes

“…Recently, Coutrot et al used the copper(I)-catalyzed Huisgen alkyne-azide 1,3-dipolar cycloaddition to end-cap a [2]rotaxane using an azide-containing mannopyranose blocking group [42,43]. The advantage of this reaction is the possibility to perform the reaction at room temperature, in opposition to the mild heating needed for the same reaction without copper (I) catalyst [41].…”

“…The Coutrot group reported the synthesis of rotaxanes containing glycosides to study the high flexibility that rotaxane architectures offer for multivalent recognition [42][43][44]50]. In all the examples they reported so far, the functional moiety (glycoside) act as the stopper for the rotaxane.…”