Design,synthesis And Applicaion Of Naphthalimide-based Organic Photocatalysts

Photocatalysis has the advantages of green mild and unique reaction modes(single electron transfer,energy transfer,atom transfer,electron donor-acceptor complex).In the process of photoreaction,photocatalyst plays a dual role of absorbing light energy and transferring electrons.The traditional metal photocatalysts,such as Iridium,ruthenium complex have some disadvantages,such as high cost,environmental pollution and difficult preparation.Therefore,it is necessary to develop organic photocatalysts with low price,easy synthesis and environmental protection.Naphthalimide is a π-plane structure with strong electron absorption and large conjugated structure.It has excellent chemical stability,photothermal stability and photoelectric properties.In recent years,researchers have developed a number of naphthalimide photocatalysts for organic synthesis,but only for a few types of catalysts and a few reactions.Therefore,it is of great significance to develop a series of new organic naphthalimide photocatalysts for organic synthesis.This paper focuses on the design,synthesis and application of naphthalimide-based organic photocatalysts,and successfully constructed aryl trialkylsilane,1,3-[2H,4H]-isoquinoldione and 3-pyrrolin-2-one derivatives.Specific contents are as follows:1.Eleven photocatalysts were designed and synthesized with naphthalimide as electron acceptor,phenothiazine,carbazole and diphenylamine as electron donor.The photophysical properties of these photocatalysts were characterized.The results show that these photocatalysts have suitable fluorescence lifetime,large dihedral Angle,suitable Gap,and wide ground and excited state redox potential.2.The silicylation reaction of N-heterarene and acrylamide derivatives was achieved by using the designed naphthalimide-based compound as photocatalyst and Selecfluor/DTBP as oxidant in an argon atmosphere of 40 W blue light,29 aryltrialkylsilane derivatives and 15 1,3-[2H,4H]-isoquinoldione derivatives were obtained with yields ranging from 30% to 87%.The method had excellent regioselectivity for N-heterarene substrates(>20:1),both the inert trialkyl hydrosilane and aryl hydrosilane could be well tolerated in cyclosilylation reaction.3.Using the designed naphthalimide-based compound as photocatalyst and PMDETA as proton source,the reduction cyclization reaction of two kinds of acrylamide derivatives was realized by using PCET strategy in an argon atmosphere of blue light,30 1,3-[2H,4H]-isoquinoldione derivatives and 30 3-pyrrolin-2-one derivatives were obtained with yields ranging from 22% to 74%.This method achieved the selective reduction of carbon carbon triple bond and carbon carbon double bond,reaction conditions were green and mild.