In Situ Generation of Wavelength‐Shifting Donor–Acceptor Mixed‐Monolayer‐Modified Surfaces

Abstract

Given the green light: Irradiation of a monolayer of an overcrowded‐alkene‐based molecular switch (see picture, left) results in generation of a mixed monolayer containing its photocyclized analogue. An efficient energy‐transfer process between these compounds is evident from the observed red‐shifted emission of the photocyclized switch.

Chirality controlled responsive self-assembled nanotubes in water

“…The structures of amphiphiles 1 and 2 contain a photosensitive overcrowded alkene unit that links two hydrophilic oligo-ethylene glycol headgroups with two hydrophobic alkyl tails. The bis-thioxanthylidene core provides a photoreactive and fluorescent functionality, 19 and the oligo-ethylene glycol units facilitate its solubility in water. The hydrophobic alkyl chains are positioned at the core structure in order to maximise interaction and to facilitate supramolecular assembly by interdigitating upon aggregation to form a very robust bilayer, resulting in the formation of nanotubular assemblies.…”

Loading of Vesicles into Soft Amphiphilic Nanotubes using Osmosis

“…Here we take advantage of the unique photoresponsive nature of the bis-thioxanthylidene core unit [41] of the amphiphile that forms the bilayer of the self-assembled nanotube.Upon irradiation with UV light (l = 365 nm), we expected that initially nicks and subsequently holes in the walls of the nanotubes would form as ar esult of irreversible cyclization of 1 upon irradiation. Here we take advantage of the unique photoresponsive nature of the bis-thioxanthylidene core unit [41] of the amphiphile that forms the bilayer of the self-assembled nanotube.Upon irradiation with UV light (l = 365 nm), we expected that initially nicks and subsequently holes in the walls of the nanotubes would form as ar esult of irreversible cyclization of 1 upon irradiation.…”

“…Finally we performed studies on the photochemical disassembly of the vesicle-containing nanotubes which showed that the vesicles inside the nanotubes can be released upon irradiation with UV light. Here we take advantage of the unique photoresponsive nature of the bis-thioxanthylidene core unit [41] of the amphiphile that forms the bilayer of the self-assembled nanotube.Upon irradiation with UV light (l = 365 nm), we expected that initially nicks and subsequently holes in the walls of the nanotubes would form as ar esult of irreversible cyclization of 1 upon irradiation. [35,41] Additionally,weexpected that after prolonged irradiation the tubes would completely disassemble.A fter as hort period of irradiation (3 min), cryoTEM analysis (see the Supporting Information, materials and methods sections for experimental details) shows the appearance of gaps in the walls of the tubes while vesicles are still present within the nanotubes (Figure 4A).…”

Fluorine‐Substituted Molecular Motors with a Quaternary Stereogenic Center

“…Am ixture of 9 (320 mg, 1.30 mmol), P 4 S 10 (866 mg, 3.90 mmol), and Lawesson's reagent (1.58 g, 3.9 mmol) in toluene (20 mL) was heated at reflux for 3h.T he mixture was allowed to cool down to room temperature and was directly purified by column chromatography on silica gel [pentane/ethyl acetate (20:1)].T he fractions containing the thioketone were concentrated under reduced pressure to as mall volume. In the meantime, as tirred solution of (9Hthioxanthen-9-ylidene)hydrazine [49] (552 mg, 2.44 mmol) in anhydrous THF (30 mL) was treated with MnO 2 (1.06 g, 12.2 mmol) at 0 8C. After 30 min, the suspension was filtered through as hort plug of Celite.…”