Photoinduced N-N Bond Construction And Synthesis Of A Variety Of Organic Nitrogen-Containing Compounds

Nitrogen-containing heterocyclic organic molecules such as N-aryl-1-aminoindole and 2H-indazole which are an extremely important important molecular skeleton structure,exist widely in all kinds of natural active molecules,drug molecules,fluorescent functional materials,and antitumor active molecules.The common methods of synthesizing nitrogen-containing heterocyclic organic molecules such as N-aryl-1-aminoindole and 2H-indazole derivatives still have great limitations,such as harsh reaction conditions,small substrate range,cumbersome synthesis ste ps,many side reactions and so on.Based on the above problems,how to synthesize the above nitrogen-containing heterocyclic organic molecules efficiently,green and simply has always been a research hotspot.In the past two decades,photochemical catalyze d organic synthesis has attracted extensive attention from organic chemists because of its high efficiency and environment friendly.A series of synthesis methods of N-aryl-1-aminoindole derivatives were developed by using the photocatalytic redox strategy and the inherent reduction ability of indolines;the dealkylation of N-alkyl amines under mild conditions was realized by photocatalytic method,and a series of synthetic methods of 2H-indazole complex bioactive molecules were developed.The main research results are as follows.The main research results are as follows.（1）This thesis reported a simple method for the synthesis of complex N-aryl-1-aminoindole derivatives without photocatalyst.Using o-nitrobenzyl alcohol and indoline as raw materials,2-nitrosobenzaldehyde was produced in situ by light promoting the self disproportionation reaction of o-nitrobenzyl alcohol,and then N-N bond was constructed by redox coupling.40 N-aryl-1-aminoindole compounds were obtained in medium to excellent yield.The method has no photocatalyst and transition metal participation,and the construction of N-N bonds can be realized by UV irradiation at room temperature.According to the control experiment and relevan t references,the possible reaction mechanism was put forward.The products bearing an aldehyde group,can be further transformed into fluorescent probe based on Rhodamine-6G derivative11,which shows a high specificity and sensitivity for Fe³⁺.（2）This thesis reported a photo-induced method for the synthesis of 2H-indazole without photocatalyst.N-methylamines reacted with 2-nitrosobenzaldehyde produced by in-situ oxidation-reduction of o-nitrobenzyl alcohol to remove methyl.65 2H-indazole derivatives were obtained in medium to excellent yields without photocatalyst and transition metal.Based on the literature and controlled experiments,the possible mechanism of the reaction was proposed.