Synthesis and Properties of Novel Photochromic Spiropyrans Having a Long Alkyl Side Chain
|Keywords||Photochromic Spiropyran Long-chain substituent UV - visible spectrum|
The photochromic phenomenon is reversible conversion process refers to a chemical species in the absorption spectra significantly different between the two forms, at least one of the conversion process is a light-driven reaction. The photochromic learn new areas formed by the intersection of the disciplines of chemistry, physics, materials, and photonics technology in the 90 years since the twentieth century. In recent years, photochromic compounds in information storage, ophthalmic lenses, electronic, optical switches and other fields there is a huge potential applications, photochromic phenomenon has become a research hotspot. At present, mostly concentrated in the light of the photochromic compound on the Shiff base, azo compounds, fulgides, diarylethenes, spiropyrans, spiro oxazine and related heterocyclic compounds. Spiropyran is a very important class of photochromic properties of photochromic compounds, because of their excellent thermal irreversibility and fatigue resistance and become the most potential photochromic compounds. The main purpose of this thesis is to simple spiropyran compounds the introduction of long-chain substituent to the synthesis of new more excellent photochromic properties of spiropyran compounds, and then study the photochromic properties of these compounds . This thesis is divided into three parts: The first part is light the photochromic phenomenon and photochromic compounds research are summarized definition of photochromic compounds and discoloration mechanism; recent years, various types of photochromic compounds Research Progress and photochromic compounds in the optical information storage, light regulation of biologically active molecules, photochromic supramolecular, protective and decorative materials and other aspects of the latest developments and applications. The second part is a spiropyran class of photochromic compounds Synthesis. The synthesis of a series of three main the spiropyran class compounds: 1) by the introduction of a long-chain alkane-substituted on the ring nitrogen atom of the indole group, and thus with the type of salicylaldehyde derivative synthesized by a series of simple-containing long chain alkane substituted group new spiropyran compound; 2) by the introduction of long-chain amide group on the benzene ring of the indole synthesis of a series of long chain amide-containing substituent of the new compound of the spiropyran class; 3) using an aldehyde group-containing spiro pyrans compound further synthesized a series of reaction with barbituric acid containing a long-chain alkyl and substituted barbituric acid group the new spiropyran compound. The target compounds of four new compounds have not been reported. In this paper, spiropyran compounds synthesized was further characterized using IR, UV - visible spectroscopy, NMR, mass spectrometry and other means. The third part is the the spiropyran compounds for the synthesis of the nature of the research. The application of UV - visible spectroscopy to study the nature of the photochromic spiropyran compounds, the results show the spiropyran compounds SP1, SP2, SP3, SP4, SP8, SP9 in ethanol solution with good photochromic properties; Lo the pyran compound SP5, SP6, SP7 in ethanol solution, but show good reversible photochromic properties. Spiropyran-based compound synthesized also having thermochromic properties. In addition, SP1, SP2, SP3, SP4, SP6, SP7, SP8, SP9 also has discoloration pH-sensitive nature. Research the different solvents on the the spiropyran compounds discoloration nature, and found that spiropyran compounds SP1, SP2, SP3, SP5, SP6, SP8, SP9 negative solvation the chromogenic effects; SP4 and the SP7 positive solvation chromogenic effect. Found by a series of photochromic properties of studied and compared with long-chain substituents spiropyran compounds and spiropyran compounds, spiropyran compounds containing long-chain substituents in solubility, discoloration nature and fatigue resistance has obvious advantages. In addition, we also studied the fluorescence properties of these spiropyran compounds to compare.