Molecular meccano for light-sensitive and light-emitting nanosized systems based on unsaturated and macrocyclic compounds

Abstract

The review presents the results of the development of an universal approach to the molecular design of light sensitive and light emitting nanosized systems with desired properties based on unsaturated and macrocyclic compounds. Within the same class of compounds, various nanosized systems were constructed using a limited number of structural fragments. These nanosized systems are susceptible to all main types of photoprocesses, such as fluorescence, photodissociation, photo isomerization, photocycloaddition, photoelectrocyclization, excimer formation, charge transfer com plex formation, the formation of the twisted intramolecular charge transfer state (TICT state), and the electron transfer. The use of photostructural transformations for controlling the complexation and mechanical movements in molecular devices and machines is discussed. The prospects of application of the new strategy are exemplified by the design of the previously unknown types of molecular switches, materials for optical chemosensors, optical data recording and storage media, photo switchable molecular devices, and photocontrolled molecular machines.

Precious metal-free molecular machines for solar thermal energy storage

“…The dyes 4a and 4c were previously described [18,21] and were used as reference compounds. To the best of our knowledge dyes 4b and 4d are new compounds.…”

“…This provides control over the “push–pull” effect in the chromophore by switching on and off states (i.e., metal-in/metal-out from the crown ligand) [20]. Further, it was found that the azacrown benzothiazolium styryl dyes 4a and 4c exhibit ion-sensitivity in the thermal cis – trans photoisomerization [18,21], a feature, which may be used in the development of thermoreversible photoionic molecular devices [19]. Crown ether-containing styryl dyes are used as sensors for dications such as Ba 2+ , Ca 2+ and Mg 2+ , or as materials for optical data storage [19].…”

Novel Linear Bis-Crown Receptors with Cross-Conjugated and Conjugated Central Cores

“…If there are double bonds such as N=N or C=C between two crown ether moieties in the receptor, the complex formation processes are accompanied by significant changes in the spectral characteristics. [4][5][6][7][8][9] The most peculiar photochemical processes taking place in these supramolecular systems with significant changes in the properties are trans-cis-photoisomerization and [2+2]-photocycloaddition (PCA) reactions. [10][11] Consequently, it is possible to control the receptor properties of bis-crown ethers through photochemical modification of the labile central moiety.…”

Absorption, Fluorescence, Photochemical and Thermal cis/trans Isomerization Reactivity of 1-Methyl-4-(4ʹ-aminostyryl)pyridinium Iodide

“…Styryl dyes are known as heterocyclic organic molecules of the general formula R−Het + −CH=CH−ArX − can undergo E-Z photo-isomerization, electrocyclization and [2+2] Cycloaddition photoreactions owing to the presence of ethylene bonds in the dye molecules [1][2][3][4][5] . The photochemical properties of styryl dyes have been extensively studied [6][7][8][9][10][11][12] ; owing to their applications in several areas.…”