Research On Synthesis Of Organic Photo-electric Reagents Containing Square Acid

Presently, more and more attention were paid to the sensitizers of organic dyes-senaitized solar cells (DSSC), the main problem of DSSC was the low-photostability and the narrow absorption wavelength in the solar spectrum. squaric acid derivatives was a class of dye with high photostability, perfect photoelectric properties and sharp absorption in Vis-NIR spectra. It had been applied in many fields. Modifing the structure of squaraine dye was the method to improve the photoelectic properties.In this article, squaric acid and series of indolenine salt were synthysized. Different squarylium cyanine dyes were obtained by different method. And the asymmetry squaraine cyanine dye was not published in the past papers. The structures of the compounds were indentified through 1H-NMR, IR, HPLC-MS methods.Hexahcloro-butadiene as starting material, squaric acid was synthysized through substitution, cyclation and hydrolyzation. Irradiation of UV light can improve 10% yield of squaric acid. Two symmetry squarylium cyanine dyes were prepared by reaction of indolenine salt and squaraine, which was identified by HPLC-MS method. Novel asymmetry squarylium cyanine was prepared by four steps reaction through the squaric acid ester-method. The feasibility of synthesis route was discussed, and all the routes were optimized.The synthesized squarylium cyanine dye with large space hindrance was difficult to aggregate among the molecules. It was prefer to be used as sensitizer for DSSC.