Branched supramolecularpolymers have been prepared from the mixture of 3-cinnamamide-α-CD (1) and 3-Nα-cinnamamidehexancarbonyl-Nɛ-cinnamamide-lysinamide-α-CD (3) and from the mixture of 3-cinnamamidehexanamide-α-CD (2) and 3. Compounds 1 and 2 formed a linear supramolecularpolymer, whereas compound 3 having two guest moieties formed a hyperbranched supramolecularpolymer. Physical properties of
Orthogonal photo-switching of supramolecular patterned surfaces
作者:Dongsheng Wang、Frank Schellenberger、Jonathan T. Pham、Hans-Jürgen Butt、Si Wu
DOI:10.1039/c8cc00770e
日期:——
Four independent states are orthogonally photo-controlled and switched by ultraviolet, blue, green and red light irradiations on micropatterned surfaces.
四个独立的状态在微图案表面上通过紫外线、蓝光、绿光和红光照射进行正交光控制和切换。
Photocontrolled Size Changes of Doubly-threaded Dimer Based on an α-Cyclodextrin Derivative with Two Recognition Sites
The hydrodynamic size of a doubly-threaded dimer of an α-cyclodextrin (α-CD) derivative bearing two recognition sites, azobenzene (Azo) and heptamethylene moieties (C7), linked with an oligo(ethyle...
Three structural isomers of monoguanidino-modified α-cyclodextrin (CD), i.e., mono(6-deoxy-6-guanidino)-α-CD (1), mono(3-deoxy-3-guanidino)-α-CD (2), and mono(3-deoxy-3-guanidino-altro)-α-CD (3), were synthesized to study equilibria for the formation of inclusion complexes with the p-nitrophenolate ion (p-NP−). The binding constants (Ka’s) for the equilibria, determined by UV–vis titration at 298 K and pH 10.6, showed that 1 with a positively charged guanidino group on the primary hydroxy side of α-CD binds the negatively charged p-NP− more strongly than the native α-CD. On the contrary, either 2 or 3, with the same functional group on the secondary hydroxy side, binds p-NP− less strongly than the native α-CD. The Ka values for 1, 2, and 3 decreased, while that for the native α-CD remained virtually constant, with increasing ionic strength of the solutions. The two-dimensional 1H NMR spectra of rotating frame nuclear overhauser effect spectroscopy showed that p-NP− included in the cavity of 1, 2, 3, or α-CD directs the nitro group toward the primary hydroxy side of the host. These results were explained on the basis of electrostatic interaction, including charge–charge, charge–dipole, and dipole–dipole interaction, between the hosts and the guest.
light: A supramolecularhydrogel is formed by the glucan curdlan equipped with α‐cyclodextrins (CD‐CUR) and azobenzene‐modified poly(acrylic acid)(pAC12Azo). The sol–gel transition and the morphology of the supramolecularhydrogel can be switched by photoirradiation at the appropriate wavelength, which controls the formation of an inclusion complex between the α‐cyclodextrins and the azobenzene moieties