Study On The Catalytic Performance Of Perylene Diimide And Pd@nitrogen-doped Graphdiyne

The development of more efficient,greener,lower energy consumption,and more environmentally friendly chemical reactions,promoting China's economic and social development significantly,has always been one of the most important topics that attract the attention of chemists.To achieve such goals,explorative studies have been conducted on two aspects in this thesis:one is novel organic photocatalyst based on perylenediimide(PDI)and its application on coupling reactions,the other is heterogeneous catalytic systems,specifically,nitrogen-doped graphdiyne as catalyst support for Pd catalyzed reduction of nitroarenes.(1)In the first part of the thesis,novel PDI based photocatalyst molecule has been designed and synthesized,with characterization on its structure via NMR(¹H and ¹³C),HRMS and XRD.UV/vis spectra and differential pulse voltammetry curve of this molecule suggested higher reduction potential than that of PDI catalyst reported by Ghosh et.al in 2014,providing a theoretical basis for its potential application as photocatalyst.Next,this molecule exhibits photocatalytic activity in the reaction of 4-bromoanisole with diboron to generate C-B coupling product,and C-C ortho coupling product with toluene,respectively.Such ortho selectivity with toluene was further confirmed by DFT calculations.(2)In the second part,Pd@PQ-GDY(Pd@Pyrazinoquinoxaline-based Graphdiyne)heterogeneous catalyst was synthesized with nitrogen-doped graphdiyne materials via“bottom-up”method developed in our group as catalyst support and K₂Pd Cl₄ as the Pd source.The prepared Pd@PQ-GDY catalyst was characterized by SEM and XPS.Then,the reduction reaction of nitroaromatics was investigated with4-nitrophenol as template substrate,and the reaction conditions such as solvent,catalyst loading,reaction temperature and reaction time were optimized.With the optimal the reaction conditions,the in-situ prepared catalyst exhibited a 5-fold increase in reaction rate for reduction of 4-nitrophenol.Subsequently,we further explored the compatibility of the substrate and found that the catalyst is suitable for the coupling of nitroaromatics and heterocyclic nitroaromatics with electron withdrawing and electron donating groups.DFT calculations demonstrate that N-doping promotes Pd(0)adsorption on PQ-GDY and improves the stability of the catalyst.