Synthesis,photochromism, and complex-forming ability of <Emphasis Type="Italic">p</Emphasis>-tosylaminobenzylideneaminospironaphthooxazine

New hybrid spirooxazine was synthesized from the 8′-amino-substituted spironaphtho-oxazine and 2-(p-tosylamino)benzaldehyde. Photochromism and the complex-forming ability toward Mg²⁺, Ba²⁺, La³⁺, and Tb³⁺ ions of the synthesized compound and initial 8′-amino-spironaphthooxazine were studied in comparison. The spectral kinetic differences in the photochromism and complex formation of these compounds were revealed.     

Synthesis and study of fluorescent properties of benzothiazolylthieno-thiophene derivatives

A number of benzothiazolylthienothiophenes have been synthesized. Spectral studies have revealed that all these compounds have fluorescent properties that depend on their structure. Dependence of absorption and fluorescence bands positions on the nature of substituents have been established. Increase of the electron-withdrawing nature of substituents led to bathochromic shift of the absorption and fluorescence bands as well as to decrease of the fluorescence intensity.     

A Kinetic Study of the Effect of Water on the Nitrogen-Fixing Ability of the Mg(OH)2–V(OH)2System

An increase in the limiting oxidation number of V²⁺ions in the presence of nitrogen in the Mg(OH)₂–V(OH)₂system was found. This phenomenon was interpreted from the standpoint of the existence of a critical size of vanadium clusters in an ion layer of the mixed hydroxide. The attainment of this critical size is necessary for the reduction of N₂and the release of H₂. This hypothesis also explains the specific activity of the system as an extremal function of the concentration of vanadium(II) at a constant Mg : V ratio. The effect of solvent (methanol–water) composition on the rate of nitrogen reduction supports the idea that the concentration of free water in the system plays a decisive role in this process. An increase in the intensity of H/D exchange in the presence of nitrogen, which is similar to that observed in biological systems, was found.     

Spectral study of the properties of photochromic polysubstituted lactones

The spectral and photothermal properties of thermally irreversible derivatives of dihetarylethenes, lactones, whose open form shows fluorescence, are studied. It is shown that the nature of substituents determines not only the absorptive but also the luminescent properties of these compounds, as well as their photocoloration and fluorescence quantum yields. The obtained dependences of the properties of lactones on their structure are important for targeted synthesis of compounds that can be used in the creation of two-photon reversible recording media with fluorescence reading of optical information suitable for application in 3D optical memory on optical disks.