Helic[6]arene‐Based Chiral Pseudo[1]rotaxanes and [1]Rotaxanes

Abstract

Chiral pseudo[1]rotaxanes and [1]rotaxanes constructed from macrocyclic arenes still remain a big challenge mainly owing to the lack of such chiral macrocycles. In this work, a new system of chiral pseudo[1]rotaxanes formed by self‐inclusion of helic[6]arene containing amide linked with the terminal tertiary amines was first discovered. Based on an atom‐economic stopping strategy, a pair of chiral [1]rotaxanes were conveniently obtained in almost quantitative yields by blocking the pseudo[1]rotaxanes with monobenzyl bromide of tetraphenylethene. The structures of pseudo[1]rotaxanes and [1]rotaxanes were characterized by 2D NMR spectra in solution, combined with DFT calculations. The photophysical properties further revealed the efficient chirality transfer of helic[6]arene to the tetraphenylethene moiety, compared to their unthreaded chiral isomers. The discovery of the chiral pseudo[1]rotaxanes allows for a wide and available synthesis of chiral [1]rotaxanes, and also opening a new avenue to the design of chiral supramolecular materials.

Chiral Bishelic[6]arene-Based Supramolecular Gels with Circularly Polarized Luminescence Property

“…The enantiomeric bishelic [6]arenes P-BH6 and M-BH6 were synthesized starting from the monohydroxyl helic [6]arenes. 61 As shown in Scheme 1, the etherification of monohydroxyl helic [6]arene P-H1 with 6-bromo-1-hexanol in CH 3 CN provided hydroxyhexyl-substituted helic [6]arene P-H2 in 83% yield, which then underwent nucleophilic substitution with N,N′-carbonyldiimidazole to give P-H3 in 70% yield. Finally, the target product P-BH6 was obtained in 42% yield by the treatment of P-H3, 1,4-butanediamine, and 1,8diazabicyclo[5.4.0]undec-7-ene (DBU) in dry THF.…”

Advances in circularly polarized luminescence materials based on chiral macrocycles

“…In 2016, Chen's group reported a new class of macrocyclic arene, named helic[6]arene. 37 In contrast to the classical calixarene and analogues, helic[6]arene and its derivatives 38–40 all showed the fixed conformations in solution and also exhibited chiral cavities. These special structural features make these macrocycles show a wide range of potential applications in molecular recognition and self-assembly.…”

Chiral Nanocluster Complexes Formed by Host−Guest Interaction between Enantiomeric 2,6-Helic[6]arenes and Silver Cluster Ag20: Emission Enhancement and Chirality Transfer

“…In our previous work, we reported a new kind of chiral macrocyclic host, 2,6-helic [6]arene [24], which performed wide applications in molecular recognitions and self-assemblies [25][26][27][28][29]. Herein, we report a pair of new chiral nanocluster complexes (G@P/M-H6) formed by host−guest interactions between the chiral 2,6-helic [6]arenes (P/M-H6) and Ag 20 nanocluster [30][31][32][33] G (Figure 1).…”