Binding Ability and Self-Assembly Behavior of Linear Polymeric Supramolecules Formed by Modified β-Cyclodextrin

Abstract

[structure: see text] The binding ability and self-assembly behavior of molecular interpenetration by newly synthesized mono[6-O-(4-formyl-phenyl)-beta-cyclodextrin has been investigated, revealing the formation mechanism of modified cyclodextrin from solution aggregation to solid linear polymeric supramolecules.

Crystal structure of the supramolecular linear polymer formed by the self-assembly of mono-6-deoxy-6-adamantylamide-β-cyclodextrin

“…; Rekharsky & Inoue, 1998), cyclodextrins also form high-order superstructures, such as polyrotaxanes (Wenz & Keller, 1994;Harada et al, 1999;Raymo & Stoddart, 1999), catenanes (Nepogodiev & Stoddart, 1998), nanotubes (Harada & Kamachi, 1994;Harada et al, 1995) and linear polymer-like (Ramos Cabrer et al, 1999;Alvarez Parrilla et al, 2002) or Cayley-tree type conglomerates (Alvarez Parrilla et al, 2000). However, although thousands of papers have been published on these cyclic oligosaccharides, the formation by cyclodextrins of interlocked chains (Raymo & Stoddart, 1999) has received much less attention (Hirotsu et al, 1982;Kamitori et al, 1987;Harata et al, 1993;Mentzafos et al, 1996;Liu et al, 2003).…”

Spontaneous Aryldiazonium Grafting for the Preparation of Functional Cyclodextrin-Modified Materials

“…In order to confirm that aggregation amβCD occurs in aqueous conditions at 1.0 mM, a solution of amβCD was prepared in ultrapure water with sonication, filtered through a 0.45 µm PES membrane filter and analyzed Figure S3). 20 For a detailed description of eq. (1) see Supporting Information.…”

“…Assuming a non-cooperative self-assembly process (pKn = (n-1) pK2, n  2), the dimer formation constant is estimated at pKdim = 2.83, or Kdim ≈ 680, in excellent agreement with phenyl-CD host-guest Ka values reported by Liu et al 21 Cyclodextrins displaying modifications with aromatic groups have been reported to form crystals via one of three pathways, cavity-tail self-inclusion, packed layers and one dimensional selfassembly. [20][21][22] Crystals of amβCD were grown from solutions in both D 2 O and H 2 O over 15 days at >3 mM concentration. X-ray crystallographic data analysis revealed that the compound crystallizes by aromatic tail penetration into the cyclodextrin cavity along a screw axis to form a linear head-to-tail supramolecular structure (Figure 1c).…”

“…Modification of the primary face to include an aromatic tail can however result in βCD in aqueous solution to readily form supramolecular host-guest complexes. [20][21][22] Complex formation can compromise the reactivity of aromatic tail groups via inclusion in the cavity of neighboring βCD units and thus potentially prevent further reactions such as those leading to surface covalent grafting.…”

Molecular daisy chains

“…56 In further studies it was demonstrated by 1 H-NOESY that also in solution hydrophobic linkers attached to b-cyclodextrins are incorporated into the cavity. 57 The strong hydrophobic binding of aromatic guests to cyclodextrins was used to assemble a variety of daisy chains based on this binding motif. 57,58 Furthermore Liu et al could show that orientation, alignment and helicity of the self-assembly can be controlled by tuning or exchanging the pivot heteroatom and the tether length.…”