Synthesis and spectral properties of a new spirophotochromic molecule.

One of the most interesting classes of organic photochromic compounds capable of reversible isomerization under the influence of external stimuli are spiropyrans.

The optical and other physicochemical properties of the isomeric forms of spiropyrans differ significantly from each other, which makes it possible to use these photochromes as sensors, optoelectronic and holographic devices, memory elements, etc. Also, an undoubted advantage of spiropyrans compared to other classes of photochromic compounds is the relative ease of their preparation and structural modification. At the same time, modification of the structure of spiropyrans by introducing various functional groups opens up great synthetic possibilities for the targeted synthesis of new photochromes with a wide variation of their spectral and kinetic properties.

In development of research aimed at expanding the boundaries of the use of spirophotochromic compounds, in order to obtain new light-controlled materials with different characteristics, as well as to study the influence of functional groups in the spirophotochromic molecule on the spectral and photochromic properties, we have synthesized a new spiropyran.

In this work, we synthesized a new salt of photochromic spiropyran containing various functional groups (-CHO, -NO₂, -OCH₃, -(CH₂)₅N(CH₃)₂*HBr), capable of reversibly responding to external influences. Photoinduced transformations, spectral and kinetic characteristics of the synthesized compound were studied.