Confused‐Prism[5]arene: a Conformationally Adaptive Host by Stereoselective Opening of the 1,4‐Bridged Naphthalene Flap

Abstract

The confused‐prism[5]arene macrocycle (c‐PrS[5]Me) shows conformational adaptive behavior in the presence of ammonium guests. Upon guest inclusion, the 1,4‐bridged naphthalene flap reverses its planar chirality from pS to pR (with reference to the pS(pR)4 enantiomer). Stereoselective directional threading is also observed in the presence of directional axles, in which up/down stereoisomers of homochiral (pR)5‐c‐PrS[5]Me pseudorotaxanes are formed.

Insights into the Self‐Filling Effects of Branched Isopropyl Groups on the Conformational and Supramolecular Properties of Isopropoxyprism[6]arene

“…Wei Jiang [5] recently reported the naphthotubes, deep‐cavity macrocycles with polar amido functions embedded inside the cavity and with the ability to complex neutral guests in water by hydrophobic effect and H‐bonding interactions [10,11] . More recently we have reported a novel class of deep‐cavity macrocycles named prismarenes PrS[n] R and constituted by 1,5‐methylene bridged 2,6‐dialkoxynaphthalene units [12–17] . Prismarenes show a π‐electron rich aromatic cavity able to form endo ‐cavity complexes with alkylammonium guests stabilized by C−H⋅⋅⋅π and cation⋅⋅⋅π interactions.…”

“… (a) Chemical drawing of Prism[n]arenes [12–17] ; (b and c) Different views of the solid state structure [14] of PrS[6] Et .…”

A facile and efficient preparation of prism[6]arene and its dual responsive complexation with 1-adamantane ammonium tetrakis[3,5-bis(trifluoromethyl)-phenyl]borate

“…Naphthalene ring-based host molecules, as one of the hottest topics, have drawn more and more attention in recent years owing to unique binding properties with different guests. 5 Prism[ n ]arenes ( n = 5, 6), 6–8 a new kind of macrocyclic hosts based on naphthalenes, were first synthesized by Gaeta and his colleagues in 2020 6 a through a trifluoroacetic acid-catalyzed condensation reaction of 2,6-dialkoxynaphthalene and paraformaldehyde in yields of up to 76%. 6 b Besides highly symmetrical prism[5]arene, they also got a new type of pentameric macrocyclic compound called 1,4- C -prism[5]arene in the synthetic process, which was a 1,4-confused isomer and showed conformational adaptive behavior in the presence of ammonium guests.…”

“…6 a , e These macrocycles exhibit very interesting host–guest properties with a series of alkyl ammonium salts to form [2]pseudorotaxanes. 6 Moreover, the per -hydroxylated prism[ n ]arenes 6 c and water-soluble prism[ n ]arenes ( n = 5, 6) 6 d bearing anionic carboxylato groups were also prepared and investigated by them and Isaacs 7 et al in detail. Later, Yang and co-workers studied the binding of prism[5]arenes to amino acid derivatives, which showed association constants of up to 10 7 M −1 .…”

Methylene-bridged naphthotubes: new macrocyclic arenes with great potential for supramolecular chemistry

“…1). [31][32][33] These macrocyclic arenes are usually synthesized through the Friedel-Crafts reaction of phenols or their derivatives with paraformaldehyde in the presence of acids and can be further functionalized to meet various purposes. 34 Over the past few decades, macrocyclic arenes have been widely studied for their application in adsorptive separation, molecular machines, biomedicine, catalysis, supramolecular polymers, and sensing.…”