Visible Light Induced The Synthesis Of Nitrogen Heterocyclic Compounds

Energy is the material base for survival and development of human.The development and utilization of energy greatly advance the development of the world's economy and human society.However,this had led to a series of energy and environmental problems.Developing new and pollution-free energy is major problems faced by humanity in the 21 st century.Light as no pollution,low prices,safe and simple new energy source,attracted extensive attention of people,has the very good development prospect.Visible light as the main part of the sun's rays,developing reasonable and appling it in synthetic chemistry,had received extensive attention of chemists.But the visible light induced organic reaction was progressed slowly,because few organic molecules can absorb visible light directly.Up to 2008,scientists such as Mac Millan developed visible light redox reaction based on metal photosensitizer,raised a hot wave of visible light induced organic reaction research.The research focus of scientists were gradually developed to the synthesis of heterocyclic compounds as well as the synthesis of many natural products from simple chemical bond rupture and produce,and developed to combination of organic catalytic,metal catalysis and other types from single visible light catalytic.Most of the photoredox catalytic reactions are mild conditions,high yield,and wide range of substrates,provide the possibility for further synthesis application.Meanwhile,there are challenges at the development of photocatalytic reaction,chemists still keep moving forward.Nitrogen heterocyclic compounds are important parts of many drug molecules and natural products,it is also a very important intermediate of organic synthetic and medicine.Developing efficient synthetic strategies,used in the study of synthetic nitrogen compounds,has an important significance.In recent years,more and more scientists developed photocatalytic reaction to synthesis of nitrogen heterocyclic compounds due to the advantages of pollution-free.Based on this,this paper developed new method of visible light induced synthesis of nitrogen heterocyclic compounds,mainly included the following systems:1.1,2,4-Triazolines are important parts of many bioactive molecules,they are also very important intermediate of organic synthetic and medicine.In this system,we used 2H-azirines and azodicarboxylates compounds to produce 1,2,4-Triazolines by one step reaction in the illuminate of blue leds and the catalysis of acridine photosensitizer.We screened and optimized the reaction conditions,and synthesized 20 different substituted 1,2,4-Triazolines.The same time,the 1,2,4-Triazolines can generate 1,2,4-Triazoles compounds under the condition of Na H.This Catalytic method in this chapter has the advantages of short reaction time,high yield,mild conditions,the substrate application wide scope.2.Nitrogen heterocyclic compounds have biological activities,are important intermediate of organic and drug synthesis.Many of the heterocyclic compounds can be made through the aromatization.In this system,we found a visible light catalytic aromatization reaction.Under visible light irradiation,through one step reaction,1,2,4-Triazolines can produce the 1,2,4-Triazoles compounds by decarboxylation reactions.This reaction has the advantages of short reaction time,high yield,mild conditions.Through the study of reaction mechanism,we found that the reaction was radical reaction.And through derivatization reaction,we found that the reaction products chold also be used to synthesis 1,2,4-Triazoles which had pharmacological activities.