Catenane Chameleons: Environment‐Sensitive Translational Isomerism in Amphiphilic Benzylic Amide [2]Catenanes

Abstract

151 a) Ricin B was purchased from Sigma b) S. Olsnes. A Pihl. The M o k d u r A d o n s o/ Torinrs and Yirirses.

An Introduction to the Mechanical Bond

“…Over the years, our own group has fabricated molecular shuttles, 174 switches, 175 push-buttons, 176 trains, 177 elevators, 178 pistons, 179 muscles, 180 abacuses, 181 motors, 182 and valves. 183 Other groups have reported MIMs as molecular necklaces, [184][185][186] locks, 187 rotors, 188 chameleons, 189 and charm bracelets 190 -the list goes on and on. These types of molecular nanostructures, whose names and representations are deliberately evocative, are known 191,192 also as technomimetic molecules.…”

Synthetic Molecular Machines

“…For example, homocircuit [2]catenane 52, acts somewhat like the two-station degenerate shuttle 35 (Sect. 7.5.4.1) [118]. In halogenated solvents such as CDCl 3 the two macrocycles interact by hydrogen bonding between their aromatic 1,3diamide groups, resulting in a "host-guest" relationship in which each (constitutionally identical) ring adopts a different conformation and exists in a different chemical environment (52-a, Fig.…”

Supramolecular templating in thermodynamically controlled synthesis

“…The saturated analog of [2]catenane 6 had been previously prepared by using kinetically controlled condensation of acid chlorides and masked phenols, but as undesired products could not be recycled the highest yield obtained was 18% (19).…”