Study On The Formation Of Phosphorous Compounds Catalyzed By Quantum Dots

Organophosphorus compounds are widely used in biomedicine,chemistry,pesticides,and other fields,due to their unique physical and chemical properties,and biological activities.The traditional synthesis schemes require the use of toxic halogenated reagents and lithium reagents,which has defects such as low atomic economy,complex operation,and other defects.Therefore,it is significant to find a simple and efficient synthesis method for the development of organophosphorus chemistry.Recently,visible-light-induced photoredox has become one of the hot points in organic chemistry.Quantum dots(QDs)have become photocatalysts with great potential due to their excellent photostability,high molar extinction coefficient,wide absorption range in the visible region,and recyclability.In recent years,QDs have been widely used in the fields of photolysis of water and photodegradation of organic pollutants,but their application in the organic synthesis field is still relatively limited.In this paper,CdSeS/CdZnS core-shell quantum dots were used as photocatalysts,the sulfur compounds as sulfur sources,and diphenylphosphine or phenyl phosphine as phosphorus sources to complete the construction of P-S bonds.This paper mainly included the synthesis and characterization of QDs,optimization of reaction conditions,substrate expansion,mechanism research,catalyst reuse,and catalyst stability investigation.When diphenylphosphine was used as the phosphorus source,the yield of thiophenol was the highest,and the yield was reduced when the functional group position was in the meta position.When phenyl phosphine was used as the phosphorus source,the reaction can be carried out with thiophenol,cyclic mercaptan,and disulfide as the sulfur sources.The QDs used in the reaction can be reused.The high resolution transmission electron microscope(HRTEM)images of the QDs before and after the reaction showed that the QDs had good stability.Besides,the possible reaction mechanism was proposed through free radical capture,liquid nitrogen deoxygenation,and a series of controlled experiments.