Synthesis And Performance Of Fluoro Substituted Perylene Diimide Derivativeswith Amine Sites

A perylene diimide derivative is a compound with a large?-electron conjugated system consisting of five benzene rings and a symmetric four electron-withdrawing groups.Because it has a lower reduction potential and exhibits stronger oxidizing properties,it can be reduced to a corresponding anionic radical by a reducing agent under certain conditions.These anionic radicals have very good activity and can form different aggregates or cause new chemical reactions.At present,research on anion radicals of perylene diimide derivatives is still rare,especially radical aggregates and radical-based chemical reactions are still very worthwhile research topics.In this paper,benzo[ghi]perylene diimide tris-anhydride?BPDI?and pentafluoroaniline were reacted in different solutions to synthesize pentafluorophenyl substituted benzo[ghi]perylene triimide?BPTI-5F?and J-type benzo[ghi]perylene triimide radical?dimer(?-[BPTI-5F]₂^2-).It was found that this?-dimer could be changed from J-type?-dimer to face-to-face H-type?-dimer by adjusting the concentration and temperature in DMF solution.Temperature and crystallization can affect the length of the?-bond in the dimer.Partial transitions can be stored and detected at room temperature.Secondly,we found that when BPTI-5F was heated in DMF,a new substance would be generated,and it would gradually increase with the progress of the reaction.Through exploration,it was found that BPTI-5F would generate a great amount of BPTI-5F anion radical in DMF solvent under heating.This radical had higher activity and could quickly undergo S_N2 nucleophilic substitution reaction with DMF.We had conducted a detailed study of its mechanism and found that the nitrogen atom in DMF acted as a nucleophile to attack the carbon atom at the para position of pentafluorophenyl group,which would rapidly undergo a nucleophilic substitution reaction to generate para-dimethylamine tetrafluorophenyl substituted benzo[ghi]perylene triimide derivative?PDMBPTI-4F?.Based on research,we tested the photoelectric properties of the product PDMBPTI-4F and found that it exhibited fluorescence quenching properties in various organic solutions.Combined with the calculation results,it was found that this compound had the property of intramolecular charge transfer.In addition,in order to broaden the scope of application of nucleophilic substitution reaction,a simpler structure of dipentafluorophenyl perylene diimide?DFPDI?was synthesized which would also undergo a nucleophilic substitution reaction when heated in DMF.Effects of nucleophilic substitution on the reaction were further explored.