Heterocycle-containing Fine Chemicals With Extinction Performance: Theory-guided Design, Synthesis And Applications

In the21st century, fine chemical industry has become the pillar industry of nationaleconomy in our country. The number of products has been up to more than30000. But there arestill many questions such as a low rate of fine chemical industry, the lack of refined products andthe environmental pollution. In the twelfth five-year period, the focus of the new productresearch of fine chemicals in China has been on the product structural adjustment and the use ofmolecular chemistry and other new technology, which is particularly prominent in fine chemicalswith extinction performance. Heterocycle-containing compounds are important fine chemicalintermediates, which showing unique properties with the traditional benzene and naphthaleneseries fine chemical intermediates because of its unique chemical structure characteristics. It hasbeen gradually used in UV absorbers, dyes and other common extinction kind of fine chemicals.In order to improve the problem of fine chemicals with extinction performance such as the poorextinction performance and the environmental pollution, this paper tries to addheterocyclic-containing structure into ultraviolet absorber and disperse dye, which will beendesigned by molecular chemistry and computer theory knowledge system. And its applicationperformance will also been compared. This paper aims at providing a complete experimentalbasis and design ideas for a fast and efficient development of extinction class fine chemicals, aswell as finding a suitable dye structure selection for hydrophobic fiber dyeing and a theoreticalbasis for performance prediction.Firstly, under the guidance of the density functional theory (DFT) and the time-dependentdensity functional theory (TD-DFT), the pyridine ketone and pyrazolone heterocyclic groups hadbeen successfully connected to the benzotriazole derivatives. Two N-heterocycle-containingbenzotriazole (BT-1, BT-2) had been designed and synthesized as UV absorbs. It was found thatthe experimentally obtained optical properties were in close agreement with the theoreticallyobtained results. Their anti-UV protection properties on PET fabric were also evaluated and com -pared with that of a common commercial benzotriazole UV absorber Tinuvin326. It was foundthat heterocyclic benzotriazole could also effectively prevent ultraviolet ray and the protectionhad a relationship with the rate of the dyeing on the fabric.Secondly, under the guidance of the solubility parameter and molecular modeling，a seriesof phenylazopyrazolone disperse dyes containing an acylamide moiety were also successfullydesigned and synthesized. It was found that the molar extinction coefficients of phenylazopyra--zolone disperse dyes containing an acylamide moiety were better than that of azo andanthraquinone disperse dyes. Their dyeing behaviors on poly(lactic acid) fibres were alsomeasured, which were compared with C.I. Disperse Yellow16, a commercial disperse dye. Theresults showed that the substituents in the dye structure largely influenced the dyeingperformances on the PLA fiber. It was found that the tertiary acylamide dyes simultaneouslyexhibited high dye sorption and satisfactory color build-up and fastness properties on thepoly(lactic acid) fabric. The study on dyeing kinetic and dyeing thermodynamic indicated thatcomparing with primary and secondary acylamide dyes at the same temperature, tertiaryacylamide dye had diffusion ability and higher standard affinity to PLA. Disperse dyes with-CONXY substituent in diazo component had higher standard affinity to PLA than that with-SO2NXY substituent.